Showing posts with label Science and society. Show all posts
Showing posts with label Science and society. Show all posts

Friday, September 8, 2017

We've never experienced anything like it!

I write this as Hurricane Irma bears down on South Florida, with the potential to be up there with the worst ever disasters from a hurricane in Florida.  I also hear some people saying they have ridden out other hurricanes and so are planning on riding out Irma.  This ridiculous notion deserves some consideration ...

In my tornado research, I spent decades becoming familiar with the climatological record of tornado occurrences in the USA.  In the process, one can't help but observe that really big, bad tornadoes are but a small minority of the 1000 or so tornadoes that hit the USA every year.  In 1998, a tornado rated F3 hit Gainesville, GA in the early morning, killing 12 people in an event that was unusual in that it was not warned-for in advance.  In the wake of that event, my colleague Dr. Harold Brooks was talking via the phone to an emergency manager in the Gainesville area and she told him (I'm paraphrasing) that she had no idea things could get that bad in Gainesville!  Clearly, she didn't know anything about the last single tornado in the USA to kill more than 200 people - the tornado that struck Gainesville, GA on 06 April 1936 (part of a two-day outbreak including a single tornado that killed 200+ in Tupelo, MS the day before).  If a "generation" is roughly 30 years, this means that the institutional memory of that awful day in 1936 had been mostly lost in, even in an agency about being prepared, within roughly two generations!  My experience says that's pretty typical.  After a big disaster, awareness is high and people are receptive to the call for preparation.  But as time passes, people move away, people die, new people move in and the local memory of disaster fades all too quickly.  Resources for event preparation are re-allocated to other projects.  Complacency grows.  All too soon, the disaster is mostly forgotten.  But the weather data base doesn't ever forget.

Studying the climatology of hazardous weather gives researchers a mental model of dangerous storms that isn't widely known in the "general public".  While I was visiting Australia in 1989, it turned out there was a flash flood event in Melbourne while I was there.  It wasn't a major event, being confined mostly to urban flooding.  I watched a TV interview the next day with a couple living in the area hit by the flash flood, and they said "We've lived here for 9 years and we've never seen anything like this!"  So they apparently believed that living in Melbourne for 9 years was going to representative of all the possible weather in Melbourne for all the rest of eternity!  And this relatively modest event was a big deal for them!

It's understandable that non-meteorologists would fail to have an accurate understanding of the occurrence of rare events.  I'm not sure how to go about fixing this shortfall in our communication of science, but here, today, with the landfall of Irma in South Florida likely in the next two days, the complacency associated with people's flawed understanding of what is "typical" for their area seems to be influential in the choices some people are making.   Ignorance of such things almost never implies a blissful outcome. 

Immediately after a major storm disaster, people are likely to want to think of what happened to them as a "freak" weather event:  something unprecedented and very unlikely.  Being hit by a major storm is a relatively rare occurrence, but calling it a "freak" event is misleading and counter-productive.  If you're familiar with the climatology of tornadoes, someplace (and possibly someone)  is going to be hit by a violent tornado virtually every year!  Violent tornadoes are rare in any one place, but they aren't "freak" events, somehow outside the range of our human experience.  Of course, they likely are outside of your own personal experience!  You could live in central OK and not be hit by a violent tornado in 1000 years; on the other hand, Moore, OK has been hit by violent tornadoes in 1999, 2003, 2010, and 2013!  The distribution of tornadoes has all the signs of being "random":  being truly random doesn't mean the events are spread irregularly but more or less uniformly.  Instead, random spatial distributions have both clusters and voids.  If we had enough data (at least 1000 years worth), we might have a very clear picture of the climatology of violent tornadoes, at least in central OK.  But we don't have that much reliable data on tornadoes before, say, 1953.  The more rare the event, the more data are required for a meaningful analysis of the danger.

It's also likely that our knowledge of Cat-4/5 tropical cyclones is similarly flawed.  A much longer period of record is needed for an accurate picture to emerge.  The climatology of major events determines such numbers as the "return period" for these events.  The more data one has, the greater the number of major events in the database and the "return period" calculation is less about iffy extrapolation and more about reliable information.  The notion of "return period" is widely misunderstood by the public but that (obviously) is off-topic for this blog.

Folks, it's just not helpful for you to have faith that your personal experience with storms includes all that could possibly happen to you.  When the storms become more intense, the less useful your experience is.  This affects the decisions you make in advance of being hit by a particular storm, and your decisions will determine such issues as whether you live through it or not.  Your choice will affect your family and perhaps even your friends.  Don't trust your knowledge of the past to be helpful - listen to what the forecasters are saying and take it seriously!  Lives hang in the balance!

Monday, August 28, 2017

Tropical cyclones pose multiple hazards

The slow-developing situation involving Hurricane Harvey has caused me to contemplate just what our weather forecast message has to be in order to be effective in mitigating the threats.  As I write this, the death toll is less than 10 people.  Every casualty is a tragedy but things clearly could have been a lot worse.  However, that isn't what I want to consider here.

There's been an effort in the last few years to try to help people understand that there are three different primary hazards posed by landfalling tropical cyclones

1.  the very strong winds near the eye,
2.  the "storm surge" of ocean water pushed onto the land by the storm's winds and low pressure, and
3.  the extreme amounts of rain.

Some hurricanes also produce tornadoes in their outer rainbands.  This event (Harvey) was forecast pretty well.  The rapid intensification was anticipated but it likely exceeded most expectations when Harvey became a Cat-4 hurricane (on the Saffir-Simpson scale of hurricane intensity) just as it was making landfall.  Evidently, the storm surge was not a very big factor in Harvey.  What was really well-anticipated was the extreme rainfall once Harvey came on shore.  This was the highlighted threat in most of the forecasts by both public and private sector forecasters, days in advance.  Arguably, in this event, it was the most important hazard, and it seems it will have become a rainfall event that, if not unprecedented, is on the extreme end of such hazards.

Every hurricane making landfall will offer some combination of these three main hazards.  Each of them carries with it a certain potential for damage and loss of life.  The actual evolution of those hazards in a particular event depends on a several factors that govern the dangers from storm winds, storm surge, and heavy rainfall.  What the storm will actually produce in terms of damage and casualties is not necessarily easy to predict with high confidence, but Harvey's main threat was forecast to be the heavy rainfall;  that was the gist of the forecasts, and that's pretty much how Harvey has evolved.

Our challenge as forecasters is to try to anticipate the hazard level for each of the three elements and seek to pass that information on to the users of our forecasts so they can make informed decisions.  In this event, as is common, some people did well in preparing themselves for the anticipated hazards, but others, not so much.  A big challenge to our forecasting community is to try to convey to the public that the windspeeds, which are the basis for assigning the Saffir-Simpson intensity category for the storm, are not always the main threat from the storm.  A weakening tropical storm may not pose much of a wind or storm surge threat but it still can be quite capable of producing copious rainfall, with its associated potential for both damage and casualties.  Although the wind threat is declining, the storm can remain seriously dangerous!

A big challenge with the threat from heavy rain is the question of what people can do to prevent becoming victims of flooding.  Obviously, flood damage is unavoidable if you live in a location vulnerable to flooding during a heavy rain episode - you can't move your home out of danger.  Many people have little or no knowledge of the actual flood threat in their particular location.  Even more challenging is what people in an area subject to flooding in extreme rainfall can actually do to protect their lives.  Evacuating the area might be effective in saving lives, but when people delay an evacuation decision to the 11th hour, then the roads will be choked and people trapped in their cars can be killed by rising floodwaters.  Some people may not be able to evacuate under any circumstances.  If you're going to evacuate to be safe, do so early or not at all!  If you choose to ride it out at home, you should have a plan regarding what to do if the waters rise high enough that even your roof is no longer safe from the rising water.  Not much you can do in that case if you don't have a boat!

Flooding is one of those hazards that if you find out you're not safe in your location, it may not be safe anywhere within miles of where you are.  By the time you figure out your life is in danger, there likely will be few, if any, good options.  Protecting yourself from flooding is not the same as protecting yourself from wind or storm surge.  What you need to do for your own safety depends on the nature of the threat, and most people have no idea how to deal with rising floodwaters.  This was the case with the awful tragedy of Katrina (which evolved very differently from Harvey) and it resulted in an awful death toll.

Frankly, most people are blissfully ignorant about how to use weather forecast information to help them make good choices.  That ignorance means they don't have the information they need to maintain situation awareness in what might be a fast-changing situation.  To rely exclusively on your own personal judgement in a complex weather scenario is to risk your life and those of others around you.  You may think you have a good bead on how to handle the situation, but you stand a good chance of being tragically wrong.

I don't believe in some magic bullet we might put into our broadcasts of weather information to cause everyone to make the right, life-saving decisions.  Essentially, everyone's situation is different - what works in one household may well fail in a different household.  We meteorologists agonize over the wording in our broadcasts of weather information but I don't think the answer to potential weather disasters lies in some magical turn of phrase.  Dealing with weather hazards involves (a) inevitable uncertainty about how the weather will actually evolve, (b) recognizing the threat early enough to take effective actions, and (c) knowing what actions will be effective in your own personal situation.  If you choose to be safe instead of sorry, you may waste some time and effort needlessly at times, but you'll be alive and well should the situation ever become life-threatening.  The choice is yours, actually.  You need to accept responsibility for your own safety and that of your friends and loved ones - learn and be prepared before the threat appears on the horizon!

Saturday, August 12, 2017

Construction practices going in reverse?

Recently, it seems that some politicians in the state of Florida are attempting to weaken the enhancements to building codes put in place following the massive disaster of Hurricane Andrew in 1992.  The hurricane revealed the vulnerability of homes built to low standards and the idea was to prepare for the inevitable return of a strong hurricane to Florida.  This current effort to weaken the codes is being led by the GOP, and it seems likely that the pressure to do so is coming from the homebuilders, who are essentially the only group that stands to gain from weakening the building codes.

Natural hazards like hurricanes and tornadoes have a tendency to fade from people's memories with time.  Immediately after a disaster, there's widespread support to do something to reduce the impact of the inevitable return of that hazard.  Sometimes, this is referred to as "closing the barn door after the horses have escaped."  Unfortunately, with the passage of time, the enthusiasm for preparing for the next hazard begins to fade.  Other ways to spend resources become a higher priority than hazard preparation.  In my experience (with tornadoes) the collective memory of disasters in communities virtually disappears within roughly 2 generations - about 60 years.  People live under the false assumption that what they've seen in their lifetimes in their location up to that point is pretty much how things will go for the rest of their lives.  Natural hazards are rare in any one place, but it's only a matter of time before they strike again.

For people who experience for themselves the horrors of a natural disaster, the memories often are still vivid decades later.  But survivors move elsewhere, older victims die, and people who move in afterwards generally haven't experienced with the survivors and victims experienced.  In our reanalysis of the Tri-State tornado, we found that the stories told by survivors are widely regarded locally as unreliable and exaggerated, whereas in our interviews with survivors, many of those stories could be corroborated by independent evidence!  I suppose it's something of an "inconvenient truth" to learn that the natural hazards can be so devastating in the place where you live.  The unpleasant reality is that if an event has happened at least once in some area, there's no reason to believe it won't happen again.  Low probability does not equal zero probability!

Interestingly, over much of Europe, building construction standards are substantially higher than in most of the USA.  This can be seen directly in the degree of damage when tornadoes in Europe hit human structures; equivalently strong tornadoes in Europe do less damage than in the USA!

Think about the relationship between construction practices and the lethality of, say, a violent tornado or a powerful hurricane.  What's responsible for most of the fatalities in a tornado?  It's flying debris ... broken 2x4s, shingles, tree branches, sometimes even cars!  There's a kind of mythology that says there's no point in strengthening building that might be hit by a tornado, because no affordable construction can withstand a tornado, right?  No, that couldn't be more wrong!

The costs to enhance structural integrity over the existing code standard of 90 mph in most of the USA, when amortized over the life of a 30-year mortgage is pretty small.  What the builders don't like is that it takes more time to build a better home, and that is what reduces their profit.  If they can build 10 shoddy homes in the time it takes to build 6 well-constructed homes, that's where they make their gains.

First of all, even in a violent tornado (i.e., one rated EF-4 or EF-5 on the enhanced Fujita scale), the most violent winds are experienced in only a small fraction of the total damage path of a tornado - typically less than 10%.  Those areas experiencing EF-3 winds or less would experience considerably less damage if their structural integrity would be enhanced over what is typical construction in the US.  Decreasing damage means less flying debris.  Shoddy construction increases the potential death toll, as well as increasing the destruction.  In most of the US, the building code requirements are such that the building should experience no structural damage at windspeeds of 90 mph or less.  The fact is that most wood frame homes built in the US are built below the code requirements, sometimes far below.  Code enforcement is pretty often woefully inadequate.  The cost of a home isn't a very good indicator of construction quality, unfortunately.  Local communities often give in to pressure from developers and homebuilders, passing laws to allow "exemptions" from code-prescribed building practices. 

When subjected to powerful winds, structural failures begin with the weakest component in the structure - often the attachments of the roof to the walls and/or the attachment of the walls to the foundation.  A 90-mph wind speed puts a tornado with that as its peak wind toward the bottom of EF-1.  Thus, even a weak tornado can cause structural damage under this building standard.  Once structural failure begins, further failures are likely - a home can be "unzipped" starting from one initial weak point.  Further, a 90-mph wind can push a home off its foundation when the walls are poorly attached - we call such homes "sliders" because they can be slid off their foundation and then utterly collapse.  Such a home can be totally wrecked by a 90-mph wind!

The building code requirements in Miami under the enhancements after Hurricane Andrew are on the order of 120 mph before structural damage will occur.  That wind speed falls about in the middle of the EF-2 category, such that much of the area experiencing EF-2 winds will have only marginal structural damage.  The area of EF-2 or less wind speed includes the majority of the damage path in even a violent tornado.  Even EF-3 winds will produce less damage with the enhanced code.

For Florida to weaken its building codes is to return to a time of lowered resistance to damage, likely resulting in more casualties.  That some of the politicians in Florida are seeking legislation to lower the standards is an indicator that the homebuilders are using their political influence to lobby the state government for the benefit of their profits.  Who else benefits from lowering the construction standards in Florida?  Weakening construction standards is an idea that should be nipped at the bud!

Monday, July 17, 2017

It struck without warning!

A recent fatal flash flood incident has led me to think over the topic of media coverage of weather-related incidents.  We in the "tornado community" frequently hear interviews with the public to the effect that tornadoes have hit somewhere "without warning" when the facts are that the National Weather Service (NWS) has indeed issued a warning.  Clearly, what this statement by some victim reflects is that she/he didn't hear that warning (or ignored it!) and then was unfortunate enough to be in the tornado's path.  I suppose they think that it was someone's responsibility to notify them personally that they were going to be hit.  First of all, it's not the responsibility of the NWS to notify personally everyone in danger.  Second, it's a fact that although technology might eventually make personal warnings possible, but at the moment, it's pretty much impossible to notify everyone who will be affected (and no one else).  The NWS might have the means to contact individuals with warning information, but the state of the art of forecasting simply doesn't permit 100% accuracy regarding who will and who won't be in the damage path of a tornado.

Most fatality-producing tornadoes these days have warnings issued at least a few minutes before someone is struck, and sometimes the lead times can be as much as an hour!  Is an hour's lead time too long?  This is a debate within the tornado community that's not yet settled and clearly requires the involvement of social scientists.  But just for the sake of the argument, let's consider some things about how warnings can be effective in reducing casualties:  for an issued warning to be effective, it requires a chain of events.  The user must

1. receive the warning by some means
2. understand what information the warning provides
3. know what to do with the warning information
4. believe the warning is relevant to him/her
5. take effective action based on the warning

All of the links in that chain must be met, or the warning will not be effective.  In the case of the recent flash flood, the people in the path of the flood evidently did not receive the warning.  It hadn't even rained at the location where the fatalities occurred - the rainfall was miles away upstream.  This is not uncommon when hiking and camping in the wild, away from TV and cell phone coverage.  If  people are to recognize the danger signs without benefit of hearing the warning, they must have experienced one or more similar events (unlikely) or have been given training in heavy rainfall situation awareness (also unlikely).  Flash floods have a special handicap relative to tornadoes:  most everyone has experienced heavy rainfall without a flash flood, whereas most people have never been hit by a tornado.  Rain seems "normal" and not very threatening, whereas a tornado is "exotic" and would automatically be seen as a threat.

A more extensive treatment of the chain of events needed for weather warnings to be effective can be found here.  There are many ways for this chain to be broken, often leading people to think that the event struck them without warning.  In the interest of their own safety, weather warning recipients should make it their personal business to learn situation awareness with respect to potential weather hazards.  The unfortunate part is that many users won't take the relatively simple steps necessary for their own safety, and seem to expect that it's solely someone else's responsibility to protect them from weather hazards.

And the fact that some particular hazard is relatively rare where the user lives and works and recreates, doesn't mean the threat is non-existent.  Tornadoes are infrequent in New England, for example, but violent tornadoes can and do occur there.  Though the danger is not high most of the time, sometimes violent tornadoes happen in New England.  Thinking it could never happen to you is the first step toward a personal disaster.  The weather is not malevolent or evil;  it's just indifferent to what we puny humans do or don't do.  At times, we find ourselves in the path of a potentially fatal hazard  Being prepared is a personal choice;  it's no one's responsibility but your own.  The NWS does its best, but there are still times when they fail to issue a warning, or issue the warning too late to be of much use to at least some people.  That's the state of the art and it should not require much to understand that a warning may not be issued sometimes.  Then, public safety depends on good luck and proper situation awareness;  i.e., recognition of danger signs even in the absence of a warning.

Sunday, June 4, 2017

What does "saving the Earth" really mean?

Some fraction of my readers will have seen this bit by the late comedian, George Carlin, about saving the Earth.  George's comedy often consisted of bashing one group or another, showing their hypocrisy or absurdity, and usually incorporated a host of valid points.  This comedy segment seems to make some valid points, but I want to discuss this as if George's monologue were a serious argument, not a comedy act.

When discussing topics related to "Saving the Earth", the meaning implied by environmental concerns is not to "save the planet" for the reason he gives: the Earth will continue, regardless of any damage we're able to inflict. The planet can and likely will "shake us off like a bad case of fleas".  But the human species is poisoning itself with the by-products of our industry, and our garbage.  Look around at all the threats to our environment:  greenhouse gases, oil and toxic chemical spills, release of radioactive materials, lost of habitat for non-human species, the danger to honeybees ... the list is long and diverse. 

If we manage to kill ourselves off by means of damaging the environment, then indeed life on Earth will go on without us, but it will be very different from life as we've known it.  Our absence will be a blessing to most of the surviving species on the planet.  We can't survive without them, but many of them will prosper after we're gone.  Our domesticated plants and animals will adapt to their life without us, or die.  In a few thousand years, most of human impacts on the planet will have crumbled to dust and be mostly invisible.  A new ecosystem will be established and little or no record will exist of all our accomplishments for good ... or that turned out to be harmful

What environmentally-concerned people really mean when they "Save the Earth" is something like "Save us from poisoning ourselves and destroying the ecosystem that sustains our lives."  It's clear that barring extraterrestrial or divine intervention, the only way we can be saved is by our own deeds.  Our children and grandchildren will have to deal with the mess we're leaving them as part of their inheritance from us.  What anger and frustration might they feel for our poor stewardship of what we inherited from our forebears?  We were given the gift of fossil fuels and we're in the process of squandering that legacy on self-indulgence and greed, and there are enough of us now that it's beginning to have an impact on the atmosphere and the world's ecosystems.  The military is concerned about that future world with anthropogenic global warming and its associated ea-level rise.  Many modern businesses have recognized the inevitability of transitioning to renewable energy sources rather than continuing the folly of our dependence on the finite quantity of fossil fuels that remain.  If these very conservative segments of our society are concerned, should we not be?

Yes, George Carlin, species have been dying out for so long as life has existed, but the present extinction rate is approaching that of an "extinction event" and, given the interdependencies we're just now learning about, this can have serious consequences for the human species. As we learn more about ecology, the continuing message is that it's not a choice between us and other species - we depend on them far more than they depend on us.  We don't know enough ecology yet to make detailed predictions, but if non-human species extinctions accumulate at an accelerating pace (which is evidently happening), the impact on humans may well become critically negative at some future tipping point.

If you're just not worried about these things, then you're contributing to the challenges to our very survival we confront ... together!  We'll either address these issues and work together to solve them, or we literally could die off together as a species.  Our transient impact on the planet will be erased and repaired in our absence over a geologically short time interval (a few thousand years).  All the things in which we pride ourselves will decay and disappear; the only evidence remaining will be a deposit of our trash and its decay products, not dissimilar to the thin layer of iridium that marks the boundary between the Cretaceous and Tertiary Periods.  This thin layer rich in iridium in the geological record is evidence of a colossal extinction event that ended the dominance of the dinosaurs and allowed us mammals to begin to become the dominant animals.  Not all that far above the iridium layer,  a deposit of plastic shards, glass, concrete dust, metal oxides, and radioactivity will depict the end of our "rule".   Our exaggerated sense of self-importance may be the source of our downfall.  In this world, there are no guarantees;  our survival literally is in our hands.  Our instincts can betray us. Yes, George Carlin, I worry about a lot of things, and try to do what I'm able to do about it.  Our current corrupt and environmentally-destructive political regime should worry you, too.

I close with the following poem by Percy Bysshe Shelley:

I met a traveller from an antique land,
Who said—“Two vast and trunkless legs of stone
Stand in the desert. . . . Near them, on the sand,
Half sunk a shattered visage lies, whose frown,
And wrinkled lip, and sneer of cold command,
Tell that its sculptor well those passions read
Which yet survive, stamped on these lifeless things,
The hand that mocked them, and the heart that fed;
And on the pedestal, these words appear:
My name is Ozymandias, King of Kings;
Look on my Works, ye Mighty, and despair!
Nothing beside remains. Round the decay
Of that colossal Wreck, boundless and bare
The lone and level sands stretch far away.”

Friday, June 2, 2017

Turning our back on the Paris Accord

The withdrawal of the USA from the Paris Accord has drawn both criticism and support - from different segments of our society.  Many of us felt it was an important first step for the world to join together to do something about anthropogenic global climate change (AGCC).  What we American do or don't do affects everyone around the world.  What goes on in the rest of the world inevitably has impacts in the USA.  We're no longer isolated bands of hunter-gatherers, and so our species has become deeply interconnected and interdependent.  Agriculture set us on the road to this interconnectedness, and industrialization moved us more rapidly in that direction.  Electronic technology is now accelerating the pace of interdependence.  Our withdrawal from the Paris accord is a profoundly disturbing step backward at a time when moving ahead to mitigate AGCC is critical for the future of our nation.

Apologists for this move are saying it was a "bad deal" for the USA.  If global climate change is worrisome to the military in this nation, is it plausible to suggest it's a myth?  If many business leaders supported our being part of the Paris Accord, is it plausible to suggest it was going to hurt the USA economy?  The US military is not exactly a bastion of left-leaning tree-hugger libtards.  Business leaders don't advocate things that will be bad for their business.  There are abundant examples now showing that reducing our dependence on fossil fuels will not bankrupt our economies, but rather will energize them.  As new technology is developed to replace the old, new jobs will be created and the economy should prosper.  In various places around the world, including American states, this is already happening.  The hard part is the transition period as we wean ourselves from fossil fuels.  To step backward away from the leadership of a movement to mitigate AGCC, will cost our nation in many ways, and is not the path to American "greatness".  It delays the inevitable transition, making the pain of transition last longer.

I'm not a climate scientist, so I have no evidence of my own to support or refute the reality of AGCC.  I defer to the consensus of my scientific colleagues who are doing global climate research.  Would you entrust your health care to someone not a medical doctor?  Would you entrust your safety to a person who has no pilot training or experience?  Why do you lend credibility to non-specialists in issues of science?  Why do you think you know as much or more about the global climate as the consensus of climate scientists?  On what basis can there be such intense political opposition to the climate science consensus about AGCC?  Insofar as I can tell, only a tiny fraction of global climate scientists are arguing the consensus is wrong.  The rest of the chorus of voices opposing efforts to do something about AGCC are not global climate scientists, but are mostly basing their position on propaganda, lies, distortions of the facts, and political machinations.  Opposition to the Paris accord is just another rearguard action against a future technology shift toward renewable energy sources that is already well underway, even here in the USA.  Opposition to progress appeals to those who feel threatened by global unity in the face of global challenges.

The current political situation in the USA is going to result in damage that will take decades to repair.  The regime in power is anti-science, anti-intellectual, supportive of creeping theocracy, contributing to the massive expansion of the income inequality gap, alienating our international allies, devastating our public education systems, encouraging xenophobia and bigotry, and on ... and on ... and on.  Each day, more damage to America is happening, so withdrawing from the Paris Accord is another step down a very destructive path for America. 

Some have said that politics is intruding into science and that isn't good for the science.  AGCC didn't become politicized by some sort of conspiracy among climate scientists.  It became politicized when it became clear that something needed to be done about the threats posed by AGCC.  There would be a price tag attached to any efforts at mitigation of AGCC, and where money is involved, there go some politicians and their corporate sponsors.  And many political conservatives wax eloquent talking of the doom associated with progress.  It's what they do - oppose progress.

Sunday, April 23, 2017

Earth Day and the March for Science

We didn't participate in the OKC March for Science - mostly because we're still recovering from our recent respiratory problems.  I'm pleased to know it was reasonably well-attended and our absence only subtracted a negligible portion. 

The widespread disrespect for science within the Trump regime and inside the halls of Congress is a component of a national malaise that didn't begin with Trump.  This trend could bring our secular democracy down.  If we lose interest in the facts, preferring lies, myths, slogans, and propaganda to a fact-based, logical understanding of the world in which we live, then our destiny is to become a second-rate nation, perhaps sliding farther toward third-rate, or worse.  A societal ambience that devalues education, science, and civil discourse is likely to fall prey to authoritarianism.  Facts will be ignored or distorted, as myths and superstitions will hold sway.

Contrary to what many people say, science is not a belief system, in the sense that science does not depend on a particular set of beliefs that are untestable and beyond question.  Scientific facts don't depend on anyone's beliefs;  whether you "believe in them" or not doesn't change the truth of their being facts!  Science uses logic and evidence to propose explanations for why the natural world is observed to be the way it is.  Experience has demonstrated repeatedly that logic and evidence work to achieve increased understanding.  Scientific explanations are always provisional, never final or "settled" in some way.  You don't have to accept them as a belief system, because they work!

Explanations based on evidence always are subject to re-evaluation and possible revision in the face of new evidence or when another explanation is proposed that does an improved job of explaining the facts as we know them at any given moment.  You certainly can choose to believe or not believe the explanations that science offers, but you can't choose to believe or not believe in the facts that were used to support an explanation.  If you disbelieve in a scientific explanation, what's your alternative explanation?  The more rigorously an explanation has been tested (often by collecting new evidence), the more likely it is to be an acceptable hypothesis.  Some ideas have been tested so many times and so thoroughly, the consensus among subject matter experts is that they go beyond a mere hypothesis to the level of a scientific "law" or "theory".  Note that the use of the word "theory" is not like some barroom conversation where someone says "I've got a theory about that!"  A scientific theory (e.g., Einstein's Theory of General Relativity or Darwin's Theory of Evolution) is a thoroughly vetted explanation.

Given those explanations of how things work, science permits the exploration of further ideas based on those explanations; if we accept an explanation, what other things can be implied using that explanation?  Validated explanations are the foundation upon which technology is built.  The fact that our technology works the way we have come to expect it to work is mute testimony to the solidity of that scientific foundation.  Our society has come, for better or for worse, to be based heavily on technology.  Those who deny the validity of science are, at their core, either (a) uncaring about the negative impacts of undermining support for science and more concerned about power or profit, or (b) they're so profoundly ignorant, they fail to grasp the significant parts of what science has given to us.  Possibly both may apply.

The evidence has shown that investment in support of scientific research is repaid many times over by the value created as a result of that research.  Yes, there are some scientific projects that seem awfully far removed from any practical application.  And no, not all scientific projects are destined to become important.  But overall, our position as a prosperous world superpower has been made possible in part by the large investments we've made over time in support of science.  Skeptics should review the book "Science - the Endless Frontier" written by Vannevar Bush after the end of WWII.  Sometimes, the most seemingly useless and impractical hypotheses can turn out to have some purely unexpected value that no one anticipated when the original research was done.  In some cases, it might be many years before some piece of research comes to practical fruition.  To limit science only to those topics that can be of immediate value is to cripple the science in the long run.  We as a nation have become obsessed with the short-term "profit and loss" analysis, and many topics that might prove valuable in the future are not being pursued for lack of funding.

Unfortunately, science is becoming a casualty in the political wars being fought over whose ideology is going to run this nation.  Topics like global climate change have become tainted with the miasma of politics, to the point where scientific facts are being denied or grotesquely misused to serve this or that political view.  This has put our nation's leading position in science at great risk.  If we fall victim to that apparent tendency, then we're doomed to fall from our world leadership position and slide down the slope toward scientific mediocrity and dependence on others to do our science for us.

This year's Earth Day March on Science around the nation is a reflection of the concerns within the scientific community for what we see happening to devalue science in our society.  Sure, it has some roots in concern for our jobs.  But of all the careers someone might pursue, I know of no scientist who chose to become a scientist purely for the profit motive, and most of use are not counted among the rich.  What we possess in abundance is a concern for the importance of truth and evidence-based critical thinking in the USA.  That's worth marching for and not based solely on our self-interest!

Monday, April 3, 2017

Wordsmithing the watches and warnings is not the path to improvement

Hard on the heels of some unnecessary storm chaser fatalities, now social media are calling into question the use of the "particularly dangerous situation (PDS)" wording in watches, and the so-called impact-based warnings (IBW) that use terms like "tornado emergency" in them.  I expressed my concerns about the initial IBW experiment a few years ago, here and here.  The juggernaut of IBW has rolled on, nevertheless.  A recent situation involved an event with a tornado headed toward a big city that triggered a "tornado emergency" warning, but the tornado dissipated soon thereafter, doing only relatively minor damage.  It's precisely this very uncertainty about tornado tracks and intensities that makes warning forecasters agonize over their decisions.  And people in the "general public" often get upset and some inevitably start whining about "crying wolf".  [I've never understood the mindset of people who become upset about not experiencing a major disaster!]

The big issue is now, and always has been, the challenge to convey uncertainty in a way that people understand the reality of the difficulties we face in issuing storm forecasts, so their decision-making actually will benefit from the added uncertainty information.  A major obstacle we face is that we as yet have no large dataset derived from interviews with a representative sample of the public.  In the absence of such information, we're reduced to guessing how to improve things.  NWS management feels the pressure to respond to the growing number of people who advocate the involvement of social scientists.  Instead of supporting extensive survey efforts to create that representative sample, all we get is hollow talk and ill-considered management decisions, like the IBW experiment.  There remain many questions to ask in surveys:  How is the current system working?  What do people consider to be a "false alarm"?  If we include uncertainty information, what's the most effective way for that information to reach and be understood by the most people?  What if we had a component in our watches and warnings that caters to reasonably sophisticated users (like emergency managers) and a different component to reach the broadest possible audience?  A watch or warning doesn't have to be either X or Y, after all - it could include a multiplicity of options.

Personally, I don't believe that wordsmithing watches and warnings is likely to be very productive.  Words have a nasty and virtually inevitable tendency to mean different things to different people.  No specific choice of wording is ever going to be universally accepted.  Even within a limited region of the nation, the diversity of the "general public" represents a serious challenge.  Further, constantly-changing technology within the "social landscape" causes that landscape to change constantly, as well.  What worked in the past may not work so well today or in the future.  This isn't a one-time challenge we can solve forever with one big push. 

We're beginning to realize that the use of PDS watches (and "tornado emergencis") may well result in people seeing "ordinary" watches as something less important than those given the PDS label.  The verification of PDS watches is somewhat better than that for regular watches - evidently there's some skill in making the choice to use (or not use) the PDS designation.  The "tornado emergency" form of the IBWs doesn't have a very good verification track record at all.  There are just too many storm-scale uncertainties for this product to exhibit much skill.  Its failures stir up controversy and there's no hard evidence to suggest that the IBW system has been a successful solution to conveying uncertainty.  What people like or don't like doesn't necessarily track with what actually works to bring about some desired outcome.

That brings up another challenge:  What's the outcome we desire?  Do we really want to be telling people what to do, and seeking a magic bullet to make people do what we want them to do?  Personally, I believe telling people what to do, say via "call to action" statements (CTAs) is not a good idea.  What people need to do depends on their specific situations, about which we as forecasters know nothing!  People should develop their own specific action plans to meet the situations they're likely to experience in a hazardous weather situation (at home, at school, at work, on the road, engaging in recreation, etc.) well in advance of the weather actually developing.  With severe convective storms, there isn't time to make such preparations when the storm is minutes away.

It's no secret that probability is the proper language of uncertainty.  It's the optimum mechanism for conveying confidence in various aspects of the forecast.  For an example of probability-based forecasts, I encourage people to review the "severe weather outlook" products from the Storm Prediction Center as an example of how to show what I call "graded threat levels" - the probability is derived subjectively and is associated with the confidence the forecasters have about their threat forecasts.  Big numbers imply high confidence, small numbers imply low confidence.  They actually have different probabilities for each of the three severe local storm event types:  tornadoes, hail, and strong winds, and they distinguish the cases with a threshold level of confidence for "significant" severe weather:  EF2+ tornadoes, hail 2+ inches in diameter, and winds of 65+ knots.  This is not just a black-and-white statement that some event will (or will not) happen - it's a complex picture that forecasters deduce from all the information they have.  There's a rather similar but less complex system for the severe thunderstorm and tornado watches.

This sort of product is what we need to develop for the short-fuse threats associated with warnings, but the difficulty I foresee with that is the rapidity with which severe convective storm threat probabilities change - they can increase or decrease markedly in a matter of a few minutes!  It would take a very close monitoring and updating procedure to capture the variability of the threat, and even if it's technically possible to do (say, using automated algorithms), with the threat changing so rapidly, would users find that helpful or simply confusing?  I suspect the latter.  The recent event referred to above exemplifies this challenge.  With a tornado headed toward a city, the "tornado emergency" call seems pretty obvious, but the reality is that the threat vanished in short order and the resulting forecast sure looks like a false alarm.  The threat was real, but it wasn't realized because of uncertainty in the storm.

We have lots of work to do, and are not well-served by hasty decisions made more or less in ignorance of the relevant facts, both in meteorology and in the social sciences.  The existing system has worked well for decades, despite its imperfections.  If we make changes, let us be confident we aren't making things worse, rather than better!

Friday, March 24, 2017

What does the public want from a weather forecast?

Note ... this is a slightly modified re-post of a guest blog here.

I’m among the first to complain about people offering their opinions about what “the public” wants from weather forecasts, rather than collecting evidence through a process of literally asking a representative sample of people.  However, the latter is not something easily done.  “The Public” is not a homogeneous block of people with equal needs and expectations.  Rather, it’s quite diverse and it’s not obvious to me even how to go about collecting a sample that might be accepted as representative (by those whose expertise is in doing such surveys).  There are some social scientists who have such expertise, I’m sure.  I might even know some of them.

Nevertheless, I’m going to go ahead and offer my unvalidated opinion regarding this issue, anyway.  I’m working with the notion that “the public”  in this context excludes all meteorologists and those who already are adept at using weather forecasts effectively.  My perception is that most people don’t pay much attention to the weather most of the time, and know little or nothing about how it works, or what we meteorologists can claim legitimately to know about the atmosphere.  When they hear a forecast, if they think it might actually matter to them on a particular day (for whatever reason), they want the forecast to be perfect so their lives will be spared (if hazardous weather is possible) and/or they won’t be seriously inconvenienced by the weather as they go about their business.

Regrettably, forecasters never know with absolute certainty exactly what’s going to happen – high uncertainty typically is present on a day when the weather is changing rapidly.  I’m not going to go into a long-winded discussion of the sources for weather forecast uncertainty, but they generally arise from the fact that the weather evolves from some starting structural state to some other state according to atmospheric physics that we know only imperfectly.  We don’t even know the starting point with absolute accuracy.  It’s sort of like putting together a complex itinerary for a trip, where we don’t know exactly where we’re starting from, and we have incomplete and imperfect knowledge of how the transportation system operates.  We will almost certainly wind up in a different place than what our original destination was thought to be, although in the case of weather forecasting, it usually turns out we come fairly close most of the time, despite being forced to use incomplete information.

Wanting forecasts to be perfect is natural and very understandable.  We think our own lives are too complex to be completely and accurately predictable, but if we can rely on the weather forecasts to be perfect, it makes our decision-making a lot easier.  Re-schedule that picnic if it’s going to rain.  Water your garden if it’s going to stay sunny and dry.  Go to the pharmacy to refill your prescription before the heavy snow flies.  In fact, this is just what's happening on most days as a result of the existing imperfect forecasting systems we use – people can and do make use of our forecasts for just this sort of decision-making despite the imperfections of the forecasts.  If someone makes a bad decision and everything goes bad for them because of the weather, they can always blame the damned forecaster!  Some surveys I’ve seen make it clear that many in the public know and understand our forecasts aren’t perfect, but still some people become upset when the weather doesn’t follow precisely what they heard in the forecast(s).  Note that in the real world, one thing forecasters do is to update their forecasts based on new weather information.  Hopefully, it won’t come as a surprise to most people that our forecasts get worse, the farther ahead they are predicting.  Conversely, we improve as the “lead time” gets shorter.  Don’t expect the forecast for weather a week in advance to have the same level of accuracy as one 12 hours in advance!

When the forecasts are changing frequently as a result of new information, this is usually because of large uncertainties on that day.  Not all days are equally difficult to forecast, of course; our forecast uncertainty is not a constant.  In fact, our uncertainty is also not perfectly predictable!

Let me tell a personal anecdote that I’ve used often to illustrate the value of knowing and using the uncertainty information in a weather forecast.  Some years ago, on a fall football weekend here in Norman, there was a slow-moving, strong front in the OKC area (about 20 miles north of Norman).  On the south side of that front, skies were mostly clear and temperatures were expected to rise into the mid-70s (in deg F) in southerly winds, while on the north side of that front, skies were overcast with low clouds and rain with temperatures in the upper 30s or so, and a strong northerly wind.  It was about equally likely the front would stay north of Norman or push a few miles south of Norman by mid-day (around the time the game kicked off).  The forecaster didn’t have the option of saying that the weather that day had about a 50% chance of either option, so the forecaster was forced to make a choice.  As it turned out, the forecast decision that morning was for warm and sunny, whereas the real weather turned out to be miserably cold and rainy.  Tens of thousands of football fans were caught in summer clothing because they accepted the forecast, and they were not happy!  Since I understood the situation, I dressed for the warm option, but carried cold weather rain gear in my backpack.  It was a simple matter to prepare for both possible outcomes!  I’ve often told this story and then asked the audience:  “Would you prefer to be offered the whole story of the forecast, including the uncertainty, or do you just want the forecast without any uncertainty information?”  I almost never get anyone who chooses the latter option!  Is that surprising to anyone?  Nevertheless, many people just want to know what’s going to happen, even though most of them understand the science doesn’t allow them to have absolute certainty.

Every forecast that doesn’t include uncertainty information is tantamount to withholding critical information from the public!  And the public needs to accept some responsibility to learn how to use that uncertainty for their own purposes – they have to set their own thresholds regarding uncertainty.  If the worst thing that could happen to you is getting a little wet, you can accept more uncertainty than if you stand to lose your life if some hazardous weather potential exists.  Unfortunately, low uncertainty, highly confident forecasts are just not possible in some situations.  We can’t predict precisely the path and intensity of a tornado, so a tornado warning generally always has relatively high uncertainty.  The same can be true for deciding just when and where winter storm weather will occur.  From a meteorological standpoint, getting the heavy snow band to within 50-100 km of its eventual location is an excellent forecast.  But that might mean the difference between heavy snow mostly in rural areas versus in a major metropolitan area.  Expecting that forecast to be perfect is just asking to be frustrated.  People can want a perfect forecast, but people in hell want a glass of water, too.  Are they going to get it?  Nope.  Likewise for perfect weather forecasts. 

C’mon people!  You know we can’t make forecasts with absolute certainty, so why keep complaining when it turns out we can’t make perfect forecasts?  The forecasts have been improving steadily, and are much better than we were even 10 years ago. The public is being well-served, as I see it.  Where we have a problem is communicating our uncertainty and the public is remiss in not working very hard in trying to learn how to use any uncertainty information we do provide.  It would be nice to figure out this bottleneck.  Sadly, I have no easy solutions to offer.


Sunday, December 11, 2016

Student loans, universities, and big business

Some recent FB posts have stimulated this blog.  From where I sit, student loan programs have evolved from marginally affordable low-interest loans into predatory loans.  After only four years of college, student loans now saddle graduates with massive debt in exchange for what amounts to declining potential for that satisfying job with good pay and benefits. It takes many years to pay off those loans, and in some cases, it's become well nigh impossible ever to be free of that student loan debt.  A college degree never was a guarantee of satisfactory employment. The only thing guaranteed is that if you don't have that diploma, you won't even be permitted to apply for many good jobs.

Thus, of late, the universities are running a loan sharking system that forces many students into deep debt and yet can promise them absolutely nothing in return, even if they graduate with distinction. Many large state universities have become businesses, not centers of learning.  Such universities now actively  discourage faculty from failing students because that can terminate the gravy train prematurely.  These corporations masquerading as institutions of learning now siphon massive wealth from the middle and lower classes into the universities, and badger their alumni into supporting the university. Their governing bodies are now often dominated by wealthy local business leaders, not people committed to and experienced in education.  The inherently progressive notion of helping students become contributing members of society for the benefit of all has been replaced with something resembling the dark vision of education embodied in Pink Floyd's The Wall, with students on a treadmill ending in a sausage grinder.

When I was in college and grad school, I didn't need any loans, so I entered the workforce basically debt-free.  My parents (middle class) were able to afford supporting my undergraduate education and I contributed some by working in the summers.  When I entered graduate school, my research assistantships paid me enough to be able to avoid student loans.  I was also the beneficiary, after my military "sabbatical," of G.I. Bill benefits.  Well-paid, satisfying employment wasn't guaranteed but those good jobs were available.  I entered the workforce in 1976 with my doctorate, and have enjoyed 40 years of very satisfying work as a severe storms meteorologist. Sadly, the opportunities I had are more or less no longer available.
 
Times have changed since those halcyon days, and definitely not for the better.  University tuition and in-residence education are decreasingly affordable.  Many scientific research institutions are now being run on what amounts to a business model and permanent secure employment is disappearing.  The way much research is done now demands short-term projects (3 years or less) with a list of deliverables, mostly "low hanging fruit" rather than risky long-term efforts with high potential value but without the luxury of guaranteed results. Increasingly, employees must find soft money for themselves even to have a job at all.  Workers hired to soft-money projects can be out of a job by the end of the funded project; last hired = first fired. Predatory capitalism is running literally out of control in our big-time universities and even in our research institutions,  forcing everyone - students , faculty, and scientists - into the business line.
 
Given the way things are going now in this nation, anti-intellectualism and anti-science attitudes are on the rise within the swelling ranks of the educationally-deprived.  This is not an environment that portends a growth of support for scientists and other intellectuals.  In fact, as it stands, they're labeled "elitists" and their findings called into question by the scientifically ignorant.  People seem to have forgotten the important role science and technology have played in the superpower status of the USA.  Investing in, and encouraging educational growth in science and technology is the "capital" that has made the nation strong and a world power.  Business people are too tightly focused on P&L sheets to appreciate the notion of investing in our youth for the long-term health of our nation.  They see only the profits from their predation and have no reason to curb their greed based on income from the middle and lower classes.  They're contributing little or nothing to our long-term stability and success.  They have no concern for the future.

Tuesday, November 22, 2016

PhDs as a ticket for admin?

Vickie and I were discussing this topic on our western trip and it triggered a lot of memories about my experiences with the educational system.  I mentioned some of this in my guide to grad students, but this includes some new thoughts since I wrote that "book."

First off, the way the education system works (at least as I've observed it) at the doctoral level is that the the primary emphasis is on demonstrating one's ability to do meaningful original research in your chosen field.  Often, a student's dissertation research is their first example of original work (i.e., not dished up as a project by one's major professor).  If the topic is assigned by their advisor, then the student will graduate as a "cripple" - having not yet shown themselves they can do research without assistance from their advisor.  A key element is that the idea for the project must be entirely their own.  From where I've sat, I've seen a lot of cases where this important requirement is not met, leaving the graduate to have to learn how to do this on the job!  This can have a bad outcome for everyone.

OK, I don't want to belabor that point here, but it's important to understand that a dissertation is often the first chance a student gets to show what they can do entirely on their own (as it would be in many research jobs they might have).  Doctoral education emphasizes research over classroom learning - or it should!  Sadly, many new PhDs go out into the world unprepared for the reality of the workplace and so often "disappear" into other situations.  As I was completing my doctoral dissertation, I recognized the absence of any experiences during my academic program that would have helped me overcome the hurdle of being able to dream up projects that are both solvable and worth solving.  There are lots of worthwhile projects that are essentially unsolvable, and lots of solvable problems that aren't worth the effort.  I think this is a teachable skill, but virtually no one teaches it.  For someone dedicating a career to scientific research, it seems to me that a course or two that offered a chance to begin to develop experience at formulating research topics would have been helpful.  My advisor wisely gave me no personal advice on how to do this, so I was forced to learn it entirely on my own.  Which I did, fortunately.  As did most of his students.

Now, however, we come to the primary issue of this blog post:  in many places of professional employment, it's becoming common at high levels of administration to require that applicants have a doctoral degree.  My concern focuses on the value of a standard doctoral program with its emphasis on scientific research when employed in a high level of administration.  I believe most PhD programs do virtually nothing to prepare a student for an eventual administrative position.  Of course, there are some people with research backgrounds who seem "instinctively" able (i.e., untrained) to be great managers.  A lot of being a good administrator is tied to having excellent "people skills" in order to support the working-level researchers (who can be quite idiosyncratic!). There also are "business" skills associated with finding and allocating resources for a research team.  Teamwork skills (as both a leader and a follower) are very important, as are communication skills (both verbal and written).  It's important for every administrator to understand that s/he can't be a success if the staff worker-bees aren't successful at their research (or whatever).  Administration is not productive work on its own, but it can be a big factor for those who actually perform the productive work for the organization (e.g., scientific research).

All too often, I see people promoted from the ranks of working-level science into admin positions for which they are grotesquely unsuited.  This usually breeds discontent among the working scientists and can be disastrous for morale.  Often, the only way to rid the staff of such incompetent managers is to promote them (and they are already well beyond their level of incompetence).  In my case, I resisted the temptation to "climb the ladder" because it would have necessitated my having little or no time to do the research I love.  Why give up something I enjoy to do something for which I have virtually no training and no desire to do?  It made no sense to me, just as having a PhD be a qualification for an administrative position makes little sense.  The primary benefit to having a former researcher in charge of a team is that they should be able to relate to the workers - but all too often, researchers promoted from the ranks become terrible managers or, at least mediocre in their position because they lack the necessary skills.

If someone aims at becoming an administrator in a scientific or technical field, there should be courses and seminars at the doctoral level that offer them some content they'll clearly need in such a position.  If a doctoral program has no such supplementary material (i.e.  in addition to the research experiences), then that diploma should not be viewed as suitable to apply for an administrative position.  Alternatively, some intensive training program for a management position could be offered - provided it's not just a "feel good" exercise that everyone passes.

Although I never had any ambition to be a manager, I've seen for myself the havoc that a bad manager can wreak within a professional program.  I may not be qualified for, or interested in having a management position, but I think I can recognize both good and bad management.  In science, my experience is that good ones are relatively few and far between.  If you find a good one, stick with him/her!

Wednesday, July 13, 2016

On disagreement's role in science

Some discussion has arisen about whether or not meteorologists who are not climate scientists can contribute to the discussion regarding global climate change.  A while back, I wrote a series of short essays about religion that I called "Leading Horses to Water".  This is one of those essays that I believe represents something we meteorologists who are not doing climate research can contribute to any discussion of global climate.
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Previously, I’ve talked about the apparent controversy surrounding the science of global climate.  The media have put out so much misinformation regarding this topic, it’s hard to imagine how the communication between the scientists and the general public can ever recover.

One of the most egregious pieces of misinformation being put forth in the media is that there is much controversy within the science regarding the main issue:  that the global average temperature is increasing, and that the human contribution (the so-called anthropogenic part) through the emission of greenhouse gases is a major causative factor in that temperature increase.  This alleged controversy is being used to support the notion that the consensus science somehow is bad science.  The level of scientific agreement about these basic ideas is nearly unanimous.  But of course, what most people don’t know, and what the media seem incapable of grasping and thereby conveying to the consumers of their rubbish, is that disagreement is an essential and never-ending component of any science!  Disagreement continues within the science, even among those who agree about the consensus findings regarding anthropogenic global warming (AGW).

Any rational argument must come out of a basis of agreement.  Without that, all one has is people talking past one another.  The basis of agreement in science can be referred to as the scientific consensus.  It establishes certain principles and bodies of evidence as having a special status.  Most scientists accept the consensus.

In a very real sense, every scientist is a salesman for his/her own ideas, competing in a “marketplace” of ideas, with the winners being given credit for improving our understanding of the natural world, and the losers being left to try to salvage what they can.  This is a perfect example of a rational free market, actually.  Ideas compete not on the public relations image, or a catchy advertising gimmick, or on pandering to the psychology of investors, but on the evidence that supports them.  If one idea provides a better fit to the evidence, then it wins a temporary victory.  I say temporary because new evidence can revive old, discarded ideas and push them to the forefront long after they were first proposed.

Science makes progress precisely because there is disagreement.  Without internal disagreement, a science is cold and dead.  Just because an individual’s idea is discarded in the marketplace of ideas (from which the so-called “consensus” emerges), this doesn’t mean that he/she slinks away utterly defeated.  A “loser” in the marketplace can redouble their efforts to uncover more compelling evidence, seek to devise an experiment that can provide a more stringent test of the ideas, or try to make a slight modification to their discarded idea to provide an improved fit to the evidence.  Ideas may be defeated now but can emerge later as new (but still provisional!) winners.  When no clear winner emerges, a host of competing ideas clash in the marketplace.  This is healthy, not some sort of scientific malaise.  Scientists improve their ideas by the criticism of their peers, and the science advances through that process.

Science establishes no idea on an absolute basis – science is not a religion, after all.  There are no sacred truths, no meaningful arguments by authority, no ultimate arbiter.  Its most respected ideas are promoted from their original status as  hypothesis to theory to law, but even laws can be superceded.  Newton’s Law of Gravity was supplanted by Einstein’s Theory of General Relativity, for example.

The AGW deniers, a tiny minority within the global climate science community and most confined to non-participants in global climate science, have failed to gain much traction in the traditional media for scientific controversy: peer-reviewed scientific journals.  Thus, they’ve resorted to using the public media, advancing themselves as the true scientists, being victimized by a vast conspiracy within the global climate change scientific community.  There are political and economic ramifications to maintaining the illusion of a scientific controversy regarding AGW, so there are others seeking to promote the deniers as persecuted champions of truth, when the fact is the whole campaign is a tissue of lies and deceit.  There is no scientific controversy regarding AGW, per se! 

The disagreement you read and hear from demagogues disguised as pundits in the media is not the wholesome, necessary conflict among those scientists who are pushing the frontiers of our understanding of the natural world forward.  The disagreement being promoted by the media springs from those who dislike the reality of AGW for their own reasons, often pecuniary or political or both.  The mere existence of disagreement in science is not news, nor does it indicate anything wrong with the science.  It’s the natural state of a healthy, active science.  But this public conflict, outside the traditional place for the marketplace of scientific ideas (in refereed journals and scientific conferences), is not about the normal scientific disagreement.  It’s about personal agendas, about politics, and corporate greed advancing its interests above the public good.  Remember the pseudo-scientific conflict about the health effects of smoking?  Perhaps you should ask yourself who gains from the promotion of claims about non-existent scientific controversy!  Is it the science?  Is it the public?  I think not.

The public has a right, nay, a need to know the truth, but people have to work and think to separate truth from falsehood, science from pseudo-science, real disagreements from manufactured false controversy.  They need to learn how to recognize the demagogues and reality-distorters from those who are attempting to help us all make important decisions for the future.

Monday, June 6, 2016

Thoughts on decision-making in the face of uncertainty

Many people struggle with the notion that weather forecasts are uncertain.  They have to make binary decisions in the course of their lives:  go on that picnic, bring that umbrella, pour that concrete - or not do those things.  Weather plays a role in many such decisions, and people seem to know that forecasts are not perfect and never have been, but they persist in being upset when they make a decision based on weather that ultimately doesn't pan out, at least as they understand the forecast.

Perhaps I'm oversimplifying this, but it seems to me that the real challenge with decision-making in the face of uncertainty is the absence of accurate uncertainty estimates.  If weather forecasts are always wrong, you could always do the exact opposite of what the forecasts say and have it work very effectively for you - a permanently, completely wrong forecasting system would be just as valuable at a permanently, completely right forecasting system!  A forecast need not be perfectly accurate to be of value to users!

Of course, no weather forecasting system is perfect and there never will be such a perfect system.  If you know the uncertainties in the forecast, there are techniques by which you can manage your decision-making so as to optimize your results.  That optimization incorporates knowledge of both the losses experienced associated with not taking some action and having that weather event actually occur, and the cost of taking that action.  This is called the cost-loss problem.  If the cost of taking some action to prevent losses from some weather event exceeds the losses if the event occurs, it makes no sense to ever take such an action.  Different circumstances demand different decisions.  Optimizing the results of your decision-making requires you to have knowledge of your costs and losses, in addition to an accurate estimate of the uncertainties.

Sadly, it's well known that people often have difficult with knowing the true risks associated with hazards.  For example, although tornadoes are very scary to many people, the reality is that the probability of being killed in a tornado is pretty low.  There are much greater risks associated with, say, food poisoning in fast-food restaurants, or driving motor vehicles.

Most people struggle with understanding the probabilities related to weather uncertainties but they have a reasonable idea of some uncertainties.  For example, uncertainties tied to their jobs are usually more or less familiar to the workers.  If your work involves manufacturing something, you usually know about the likelihood of producing a defective product.  Similarly, uncertainties related to your home are often reasonably well-understood.  You generally know something about the chances that your water heater will fail.  When the uncertainties pertain to the weather, most people generally have no idea what those probabilities might mean and how to use them to make choices.  It's not that they need to know abstract probability theory to begin to grasp what weather probabilities (the language of uncertainty in weather science).  Most forecasters never did very well in probability and statistics!!  But people can use a concept effectively even when they don't actually follow the abstract mathematics.  Card counters in blackjack are making effective use of their knowledge of uncertainties - so well that casinos don't allow card counters to play!

Part of our problem is that traditionally, weather forecasts have not been expressed in probabilistic terms.  The use of probability of precipitation (PoP) was introduced in the mid-1960s but there never was any sort of public information campaign to help forecast users understand them - an awful oversight!  Curiously, even many forecasters don't know the proper definition of PoPs, although with experience and some feedback, they can become very adept at estimating their uncertainties in terms of PoP.

The end result of having little or no understanding of weather forecast uncertainty - and all forecasts are uncertain to a greater or lesser extent - is that forecast users will develop all sorts of heuristic methods for making choices.  Many of these are likely to be rather less than optimal use of the information the users have.  And apart from PoP and some severe weather forecasts, uncertainties are not mentioned in forecast texts and broadcasts.  Since that information is known, at least in the minds of the forecasters, this amounts to withholding needed knowledge from the users!  If we don't include the uncertainty information in some form, users must guess about that uncertainty, and their guesses often are wildly incorrect, such as thinking that forecasts are "wrong" the majority of the time.

Users can handle decision-making in the face uncertainty only when they know the uncertainties reasonably well from being familiar with them.  Unfamiliar uncertainties (as are those in weather forecasts) are inevitably mysterious and are a source of anxiety in decision-making as well as the source for cynicism about the forecasts.  People demand, unreasonably, that forecasts express the weather in binary terms - this event either will or won't happen - even though they must already know forecasters can't do that very well all the time.  What they evidently want is for weather forecasts to make their complex decisions (including much information that forecasters can't know anything about) for them.  Forecasters simply can't and shouldn't do this. We need to help our users understand more about our uncertainties or this situation will never improve, and users will continue to get less value from weather forecasts than what forecasters are capable of providing. 

Sunday, May 15, 2016

Can we do away with tornado F/EF-scale ratings?

Let me state at the outset that I have no doubt meteorology will be saddled with the curse of F/EF-scale ratings for a long time to come, so this is mostly an exercise in futility.  Why do I dislike these ratings?  The main problems I have with them are discussed here.  The essence of why they bother me and seem so counter-productive is that they represent an effort to provide a simple summary measure of something that's very complex.  I suppose having a rating is better than not having any information about the intensity (i.e., windspeeds) in a tornado and thereby assuming they're all the same.  But that's not the only choice we professionals have.

Consider just one damage indicator, say a particular type of framing attachment in a typical American frame home.  A host of complex issues are associated with the failure of that particular type of attachment, such that if you could test a large number of such attachments by subjecting them all to the winds in a wind tunnel wherein you knew the windspeeds accurately, you would find that there's no single value of the windspeed that would cause that type of attachment to fail.  Instead, because each such attachment is a unique combination of components, the failure of that type of attachment would be associated with a range of windspeeds.  In doing a survey of tornado damage, you would not be able to know precisely what windspeed caused the failure of that attachment - rather, failures would occur within a range of windspeeds.  This is true regardless of what damage indicator you use.  At best, a given amount of damage can never be said to have a single, precise value of windspeed that would cause that amount of damage.  Thus, in the absence of any way to measure the windspeeds that produced that damage, the best one can do is know the distribution of windspeeds that cause that amount of damage.  You might choose the media (or the mean) within the distribution to represent some sort of a guess, but doing so is intrinsically wrong from a scientific viewpoint.

Further, we know very little about the actual spatial and temporal distribution of windspeeds in a tornado, even for those few tornadoes sampled with mobile Doppler radars.  It's common to idealize the airflow in tornadoes using some simple model, such as that of a so-called Rankine Combined Vortex.  All one needs to do to convince oneself that most real tornadoes probably don't fit that model very well in detail is look at some tornado videos.  The actual winds in a tornado, especially those with multiple vortices, can be vastly more complex than any simplified vortex model.  It's these real winds that interact with real objects in the path of the tornado to produce the observed damage.  This is a very important fact that makes it currently impossible to know by objective measurement what windspeeds are associated with any particular element of damage.  The time sequence of winds experienced by some damage indicator simply isn't known.  Plus the presence of debris in the wind - which alters the wind distribution - adds an additional level of complication.  Thus, a complex, debris-laden windfield interacting with objects whose failure points cannot be known precisely makes this whole issue vastly more complicated than what can be expressed by some single summary number.  Reality is staggeringly complex and the idea that one number can offer much insight is too absurd to consider.

Except that's precisely what the existing F/EF-scale ratings are trying to accomplish.  There's no hope that in what remains of my life and for the foreseeable future, it will ever be possible to have wholly objective, high-resolution measures of tornado windspeeds.  Yet, we continue to use these rating systems with hard boundaries between categories, and category boundary values that are essentially arbitrary and without any real significance.  Is it really plausible to say that an estimated windspeed of 199 mph (EF-4) is actually distinguishable from one of 200 mph (EF-5)?  Can we really make such a distinction based on various observed levels of damage to damage indicators?  Does it make sense to call a tornado an EF-5 based on a single damage indicator at one point in an extensive damage path?

The science of tornadoes is riddled with uncertainties, so there can be no plausible reason to accept as meaningful some single summary measure based on making numerous simplifying assumptions and creating arbitrary categories.  Science has learned how to make those uncertainties work for us in coming to conclusions, via the methods of statistics.  If we're going to have a scientific data base that's of much help to the science, it shouldn't be using the F/EF-scale rating of tornado windspeeds as some sort of meaningful measure.  Distributions of estimated windspeed, probabilities of windspeed values associated with particular damage observations - these are much more appropriate tools with which the science can work.  Every professional knows already that such ratings have many problems and are a very crude way to think about the phenomena.

I get that the public may not care about the subtleties here.  There may well be pressure to produce some sort of summary measure for the masses of non-scientists.  Fine.  Let someone decide how to do that, hopefully based on some reasonable application of science and engineering.  But professionals surely can do better than condensing all the complexity and accompanying uncertainty into one summary number.  I say we should do away with the ratings, at least at the science level.

Wednesday, April 27, 2016

A "busted" tornado forecast, in retrospect


26 April 2016 (coincidentally, the 25th anniversary of a major tornado outbreak in the Plains) is a classic illustration of the challenges associated with tornado forecasting.   The connection between the synoptic-scale weather systems and the occurrence of a major tornado outbreak ("outbreak" means different things to different people – there's no formal definition) is complicated and depends heavily on details at smaller scales.   One can get the synoptic-scale forecast mostly right but the development of tornadic supercells can be quite sensitive to the detailed structure and evolution at scales ranging from the size of a single storm to features on scales thousands of km across.  In meteorology, getting all of those details exactly right in the forecast is something that more or less never happens.  We can forecast tornado outbreaks in advance with varying levels of confidence, but they're never a sure thing.  Sometimes the details conspire to ruin the forecast.  What looks portentious, even a few hours in advance, can unravel quickly, such that the event doesn't unfold as forecast.

This case reflects certain facts about how severe storm forecasts work at the Storm Prediction Center.  The "culture" of the office contributed to the way the forecasts evolved.  If the situation looks like a possible outbreak, there‘s pressure from a variety of sources to give advance notice of upcoming tornado outbreak potential.  Once a forecast is issued, subsequent forecasts tend to maintain a relatively high level, even when new information (or a new forecaster) might suggest a downgrade of the forecast.  There's a reason for that:  users are uncomfortable with vacillation of the threat level, and if the threat is downgraded, and then even newer information means a return to enhanced threat, the indecision can come across as incompetence.  In other words, it can be unwise to back off the threat level.  Moreover, there's an asymmetric penalty for missed forecasts:  a false alarm for an event that never occurs can't result in human casualties and destruction, whereas an unforecasted event that kills people can be cause for investigations and possible disciplinary action.  This makes overforecasting almost inevitable.

In this case, there were some indications from the forecast models that the probability of a major tornado outbreak was decreasing as the fateful day approached, but the outlooks continued to raise concerns that a tornado outbreak could occur.  I don't necessarily see that as an error; it's realistic given the current state of our science.  An interesting facet to the case is that in the morning outlook on the day of the event, the forecast tornado probability was still only 10%.  The outlook was not upgraded to "High Risk".  I believe this is a plausibly accurate reflection of forecaster uncertainty.  However, the media were continuing the drumbeat of concern for a major event - the issue of the media is not going to be dealt with here.  Technically, a severe weather outlook is not focused only on tornadoes, and the nontornadic aspects of the forecast worked out pretty well.  Therefore, my comments here are restricted only to the forecast of a significant tornado outbreak with multiple, long-track, strong to violent tornadoes (EF2-EF5)

In my view, and this is purely a personal opinion, the biggest "mistake" from the SPC was issuing a PDS ("Particularly dangerous situation") watch in the early afternoon.  This was not warranted by the information of which I was aware (I was out storm chasing).  Whatever explanation might be offered in justification of this decision is in direct contradiction to the observed events.  I'm sure if offered a "do-over", the choice would be not to make it a PDS watch.

Make no bones about it.  Tornado forecasting isn't an easy job and perfection is out of the question.  I mean no disrespect to any forecaster involved in this event but we have to accept that the outcome is generating some backlash that's quite understandable.  Uncertainty is inevitable and probability is the language of uncertainty; by whatever verbiage we use to express it, we meteorologists need to communicate our uncertainty to our users such they accept the real capabilities of meteorological science as applied to the task of forecasting tornadoes.  By all means, we need to find out how to communicate with our users so that they understand our message, and know how to respond in the appropriate way to our weather forecasts.  We simply can't provide a 100% level of confidence in the forecast information we provide.  Our users must learn that they bear some responsibility for their own self-interests.   Weather hazards can present people with life-and-death situations, so in their own best interests, they need to pay attention and learn how to make the best use of what the science allows us to provide.