The Climate in Emergency

A weekly blog on science, news, and ideas related to climate change


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Come On, Baby, Light My….

Obviously, the Wine Country fires are yet another of the many signs of the coming climate Apocalypse, right?

Well, maybe.

I’ll spare you all the suspense and say yes,wildfires probably are increasing due to climate change, but the picture is a little more complicated than it might appear. Let’s explore some of these extra details a bit, shall we?

First of all, a fire season can be “bad” in many different ways, just as a hurricane season can be, and in order to even assess whether fire seasons are getting worse, we need to first decide what kind of “bad” we’re even looking at. For example, a fire season can be bad because:

  • There are a lot of fires
  • A lot of acreage burns
  • The fire season is very long
  • The fires are unusually hot, thus causing more damage per acre burnt
  • Fire behavior is less predictable than normal, making the fire harder and more dangerous to fight
  • More places humans care about burn
  • Fighting fires costs more than usual
  • An unusual number of people die in fires

Obviously, several items on the menu can occur at the same time–a year might see a lot of very large, hot fires that behave unpredictably, kill lots of people, destroy lots of property, and cost a lot of money during a time of year when fire danger is normally low. But it’s also possible to see a huge number of very small fires, a small number of very large fires, or a season that seems bad only because beloved places burn, while fire behavior is otherwise fairly mild.

Also, some of the variables in play are clearly linked to climate, such as the length of the fire season. But other forms of “bad” are partly or wholly caused by other factors, such as where suburban development is occurring, how forests are being managed, and how wildfires are being fought.

As with hurricanes, the challenge is to tease out a consistent, relatively uncluttered dataset so you can compare apples to apples from year to year–for enough years for statistical relevance. Unfortunately, most of the articles don’t address where their information is coming from, even when the site is quite reputable, so it’s hard for a non-expert like me to judge how much we really know and how much is logically sound conjecture.

Wildfire Is Getting Worse Because of Climate Change

A simple online search brings up lots of articles on how climate change is definitely making wildfires worse (meaning “longer and more intense”). There are several mechanisms involved. Most directly, higher average temperatures drive more evaporation, and earlier snowmelt, meaning that fuels are drier for a greater part of the year even if precipitation remains the same. Indeed, fire seasons are usually two months longer now than they were a few decades ago. Longer fire seasons mean more fires and also a greater drain on national firefighting resources.

A hotter climate also increases the chance that firefighters may have to work in dangerously hot weather. Hot weather at night can be especially damaging, because heat injury is cumulative. If the body can’t rest from the heat, then heat stroke becomes more likely.

Changes in precipitation patterns, another aspect of climate change, are also important, and not only because some areas are increasingly vulnerable to drought. Climate change involves a concentration of precipitation, so that a greater proportion of the rain that does fall comes in intense cloudbursts, with longer gaps in between. Even if average precipitation holds steady or goes up, this “never rains but it pours” situation is bad news. The rainstorms trigger lush plant growth, which then dries out in the long periods between rains, increasing fuel loads.

The number of acres burned per year has gone up over the past forty years, although the year-to-year variation is very large as well and tends to complicate the picture.

And of course, changes in land-use patterns play their own roles, since there are more houses being built in wooded areas than there used to be, and those houses burn if the woods do.

Wildfire Might Not Be Getting Worse

I’ve also found a few articles arguing that wildfires aren’t getting worse at all. One article argued that America’s forests are getting too dense because there aren’t enough fires and that Congress should provide immediate relief by encouraging logging. Unfortunately, I have not been able to re-find that article, so I can’t verify either its methods or its politics. The other simply points to the lack of trend and leaves it at that.

In some ways, it’s a pretty solid piece–it even links back to several original research papers, and the website, which belongs to a group of public radio stations has no obvious political agenda. A close reading of the article, and its sources, resolves the apparent contradiction.

The author, Tom Banse, acknowledges that fire seasons have been trending worse in recent decades, as other authors describe, yet he frames his own article as providing “contrast” by discussing three scientific papers that “question that prevailing wisdom” by looking at longer time scales.

Time scale is important. It’s possible to create trends out of nothing, or erase trends that actually exist, simply by looking at data from either a too-short interval or a too-long interval. Reading Mr. Banse’s article, it looks as though such obfuscation may be occurring with respect to wildfire, at least in the Western United States. Reading the papers he cites….

The link to one of those three papers is broken. The other two do say the things that Mr. Banse says they say, but not in any way that contrasts with the narrative of climate-induced fire severity.

One paper (actually a report by the United States Forest Service) concludes that, at least in some parts of California, fires were more frequent before the European-American conquest than they have been in modern times, defined as since 1908. In other words, it does not comment at all on changes in fire frequency over the past forty years–the study did not look at trends at all, at any time scale. Instead, the study’s methods involved dividing the study area up into ecologically defined sub-units and comparing the fire frequency for each unit before conquest to the fire frequency after 1908. Thus, all the fires in all the years since 1908 are subsumed into a single number.

There is nothing wrong with that method, but it was designed to address a very different question than the one Mr. Banse is using it to address. It’s a non-sequitur that happens to include the requisite words that wildfires used to be more frequent.

The other paper demonstrates that prior to conquest, fires were often more intense than conventional wisdom among conservationists maintain. Note that the authors of this paper aren’t talking about modern fire behavior at all. They are comparing their understanding of pre-conquest fire severity with somebody else’s understanding of pre-conquest fire severity.

Mr. Banse does quote one of the paper’s authors as saying that fire severity is less now than what “early settlers were dealing with,” but it’s unclear where this quote comes from–it does not come from the paper, since the language of the quote is not formal. Without the original context, we can’t tell what Dr. DellaSala was really talking about in his quoted remarks, or what information he was basing his remarks on. He does not seem to be arguing against the idea that climate change is causing larger, hotter, or more frequent wildfires, only that, from a strictly ecological perspective, more fire isn’t the disaster people seem to think it is.

A very interesting point–but relative to Mr. Banse, it’s another convenient non-sequitur.

Does Tom Banse have a climate-denier agenda? Maybe. The article is certainly structured as a counterpoint against the use of wildfire as evidence of the reality of climate change. I suspect that in the three years since its publication, it has been linked to by climate deniers more often than by the climate sane. But without more information, I cannot judge Mr. Banse. It’s possible he just felt that a counterpoint to prevailing wisdom seemed more interesting.

What’s Going on with Wildfire?

The actual fire we see is a result of a combination of climate, land management (including fire management), and other factors. The research Mr. Banse references hints at that complexity, though probably not in the way he intended.

While the quoted researchers seem to treat the conditions found by settlers as natural, it is likely that the lands in question were being managed intensively with fire prior to conquest–fire was a common management tool in many areas of North America, though I don’t know the details for the areas in those studies (if we don’t normally think of Native Americans as having their own land management practices, it’s because we’re racist; the idea that any part of the American was untouched by humans prior to white people showing up implicitly assumes that Native Americans aren’t human). After conquest, management with fire stopped, and was, within several decades, replaced by active fire suppression (when I was doing fuels reduction cutting in Arizona, I was told that grazing by cattle dramatically reduced fire frequency well before fire suppression began–close-cropped grass did not carry flame well). Of course there were fewer fires–that was the idea.

Decades of fire suppression increased fuel loads dramatically, thus increasing fire risk. Land managers have in more recent decades responded by conducting controlled burns and by allowing some fires that do not threaten developed areas or infrastructure to burn freely. Between one thing and another, fire frequency and severity have increased again, and would have increased anyway whether climate change intervened or not.

It’s not that I don’t believe climate change is a factor–in fact, I don’t see how climate change could avoid being a factor, given that it directly affects both fuel load and fuel moisture content, as well as making firefighting more dangerous due to the risk of heat stroke, as mentioned. But neither the fact that more acreage is burning, nor the fact that this year’s fires are particularly bad is itself the proverbial smoking gun.

What I’d like to see–and I’m sure this exists, I just haven’t seen it this week–is an article, written for a general readership, that presents the changes in fire behavior that result from climate change as separate from those that result from changes in land management and fire management practices. And I mean observed changes, not simply a discussion of what climate change ought to be doing based on our general knowledge of it.

That Mr. Banse may have had an agenda doesn’t make him wrong; that he is wrong makes him wrong. Most people have an agenda of one kind or another, and even those who profess to being utterly objective generally reflect somebody’s viewpoint or priority system (for example, who is paying for their objective scientific research and why?). The point isn’t to avoid those who have agendas, the point is to avoid lies, misleading statements, and agendas that are irrational, dysfunctional, or immoral in some way. Mr. Banse was honest enough to give us the tools to evaluate his talking points–he included links to peer-reviewed scholarship. That’s why we can say that his article was close to meaningless. I find myself wishing that more writers whose agendas I might like better were equally helpful and honest, if only so I could be certain they are right.

So, to summarize: wildfires are burning more acres per year, on average, than they did when I was born, and fire seasons are longer. Fires are also more dangerous to fight because of the increased likelihood of heat waves. Climate change is part of this picture, because it gives us longer summers and longer dry periods between wet periods. But other factors are also changing fire behavior, and at the moment one of the areas that happens to be on fire is beautiful and famous and populated, so we really care about it.

And at 11:31 PM of the day I’m supposed to post this, I can’t tell you what the relationships among all those factors is, or whether anyone knows.

 

(Note; actually, someone might know, and that someone might be me; I’ve written about fire in this blog before, but since I’ve been chasing information online today without much success, I haven’t had the time to reread my own work and hunt down my earlier sources. The result is this article that comments on the need for better science communication as much as on climate change itself)

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How Do You Solve a Problem Like Maria?

As I write this, it seems likely that Dominica has been destroyed, given that the island has been raked by a Category 5 hurricane–that’s Maria, in case anyone has lost track. The storm will hit Puerto Rico and St. Croix, but where it will go next is unclear. A strike to the mainland US cannot be ruled out, possibly at Cape Hatteras and maybe again at Cape Cod, but at least it will not recapitulate Irma or Harvey.

I’m underneath a hurricane right now myself (Jose), though only the edge, so conditions here are not bad. The weather is blustery, with occasional rain. The main part of the storm is out in the Atlantic, and it seems likely to sty Although I wouldn’t want to have to go out in it, but we’re pretty safe right here, at the moment. The important thing to notice is that we’ve had three major hurricanes in the Atlantic that made landfall within just over thirty days.

This is turning out to be one of the years when climate change is more obvious.

I want to emphasize, though, that weather is still variable, and that if next year we have hardly any Atlantic hurricanes, climate change will still be just as real. If we don’t want deniers using random cold snaps to fuel their arguments, we should refrain from equivalent lapses of logic. The problem of Maria and her colleagues is not that they prove climate change (they may, but so do lots of other factors) but that they illustrate it.

This is what is coming. This is what normal is going to look like.

I know I keep saying this, but it keeps being true, and honestly it just seems silly to write aout anything else as yet another Cat 5 hurricane bears down.


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Catastrophe?

In case anyone hasn’t noticed, there’s a real possibility that we could lose another city to a monster hurricane next week.

(Yes, we haven’t lost Houston permanently, just like we didn’t lose New Orleans permanently after Katrina. I don’t mean to imply otherwise, only that we’re looking at very big-deal phenomena, here)

Hurricane Irma is, as I write, the most powerful storm ever recorded in the Atlantic (Pacific storms have been stronger) and it’s pointed, more or less, at Florida. It will certainly wreak havoc in the Caribbean, although which islands will be most strongly affected is still unclear. The various computer models all agree that it will head more or less arrow-straight for the Straits of Florida, when it will abruptly turn some species of north. Why will it turn? I haven’t found an explanation. It’s tempting to say that the power of the wishes and prayers of the people of Houston are having an impact, but if wishes and prayers worked like that, Houston wouldn’t have flooded to begin with. Probably there is an entirely prosaic explanation the TV weather people aren’t bothering to talk about. The important part is where will Irma go after it turns? It could enter the Gulf. It could buzz-saw up the East Coast (and hit me, not incidentally).

Or, Irma could send a 20-foot storm surge across Miami, a city of almost six million people less than seven feet above sea level–one that’s already starting to flood regularly on the highest tides.

I want to be very clear–I’m not saying that Irma will destroy Miami, since the meteorologists aren’t saying that yet, and they know better than I do. I’m also not saying that Miami, which might well escape, is somehow more important than Antigua and Puerto Rico and parts of Cuba, and the other places that almost certainly won’t escape. This is going to be very, very bad somewhere, regardless of where that somewhere turns out to be. What I am saying is that this is how national-scale climate disasters are going to happen, maybe this year, maybe in the future.

If Miami floods catastrophically next week (or if New Orleans floods again, which is also possible), the United States will be dealing with three such floods simultaneously (the third is Baton Rouge, which flooded due to a rather bizarre weather pattern last year and has still not fully recovered), two of them in major cities–and the hurricane season still has two months to run. A third major hit this year is not out of the question (say, New York? or Boston? or Washington DC?). I don’t mean to make like Chicken Little–just because catastrophe sounds plausible does not mean it’s going to happen–and the United States, as a nation, is very rich and can probably absorb all these costs. State and local officials will likely do excellent jobs to protect life and limb in the teeth of yet another storm, and together we will get through this. But you can see how the costs of multiple disasters can pile up. And then pile up again.

Climate change makes disasters more likely.  This summer may be showing us what the future looks like.

But is that the same as saying that the frequency of disaster has actually increased, yet. The way the laws of chance work, a clump of bad luck doesn’t necessarily mean anything. You can get heads three times in a row–the unusual run is just balanced out by more tails, if you flip your coin enough times. Humans are notoriously bad at telling the difference between a clump of luck and actual meaningful pattern, which is why we invented statistics. Personally, I’m guessing that we are in the midst of meaningful change, but as I’ve written before, I haven’t been able to find real figures on whether our rate of extreme weather events is changing. I am fairly confident that such figures exist, and I wish they were easier to find.

Even without figures on whether extremes as a group are occurring more often, we can look at certain types of extremes. Hurricanes, for example, have been studied extensively but with difficulty, because of problems in the historical data. Whether hurricanes are getting more frequent is therefor hard to say, though the proportion of hurricanes that grow to category 4 or 5, or that reach higher latitudes, does seem to be increasing, and storm surges are definitely getting worse because of sea level rise.

But say there’s a category of disaster that could be being increased by climate change but isn’t, yet. So? What we know is that climate change is real and that it makes catastrophe more likely. Must we wait until all types of catastrophe are obviously worse before we act?

 


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Many Waters Cannot Quench

I was going to write something to do with my fortieth birthday, which has just occurred, and offers various possibilities for potentially interesting riffs on life. I had some ideas. But then Hurricane Harvey got in the way, as hurricanes tend to do.

To be clear, I am not personally being impacted by Harvey, I’m in a different part of the country, but I have friends in Texas and I’m thinking of them. And, when any form of weather produces “catastrophic” damage (the term being used by the experts), I really cannot ignore it.

Voices in the Dark

Social media is an odd but effective way to watch an unfolding disaster. Not that it can replace journalism, we do need fact-checking, context, analysis, etc., but the unfiltered voices of the multitudes add an immediacy that the news alone cannot match.

I’m a visual thinker, and when information comes to me in a non-visual format, such as radio or text, I often visualize darkness. Thus, my experience of Superstorm Sandy, aside from its brush through my own neighborhood (racing the storm home in the middle of the night, wind starting to buffet the trailer at three AM on a deserted highway in Delaware) was of voices crying in the dark, on Twitter. The one begging for a generator to keep her ventilator going, somewhere in New York, still haunts me. Did she live the night? I don’t know.

This time the voice in the dark has been a self-appointed citizen journalist, my friend, Bridgette Mongeon. I quote excerpts from her throughout this article with her permission.

Dear friends and family,
Thank you for your prayers during this approaching storm. The rain fall that is expected in Houston and all along the Texas coast is astronomical. I have lived in this home through Ike 2008, Allison in 2001, and our first year we moved in was Alicia 1983. Allison, was a tropical storm that played havoc in our area. Allison was just before 9/11 and was a double whammy on our psyche that I still feel rise up in my belly. Somehow the two are connected and re-stimulating.

I do not know what to expect for my immediate neighborhood. This area has had a tremendous influx of new building and I have no idea what that means for the flow of that much water. I am not evacuating . So many have to evacuate from the south. We have been asked to keep off the roads. I also need to keep an eye on the studio as well as my home…. Harvey is stalling and picking up intensity, which means it could hit land as a cat 4. If people in Houston expected a cat 4 or 5 we all would have been boarding up the windows…. Either way, we are on the east side of the hurricane, which we in the south call, “the dirty side” This, as it sounds, is not favorable…. Prayers go to all the people south of us and along the coast. They are evacuating quite a few people today. Evacuations can often be a challenge and dangerous events because of the amount of people. It is their safety that is priority right now.

Be safe Texans. Thanks for your prayers and well wishes everyone else. I’ll update when and if I can.

August 25, 8:13 AM

Since then, she has been posting regular updates for both local residents (tornado warnings, notices of shelter openings) and people farther afield (a detailed description of drainage patterns in the Greater Houston Area). She still has electricity, internet, and news. Not everybody in her area do, and some evidently have internet but not much else, so she’s acting as an information hub. Even the official journalists are being impaired by the storm–one of her local TV stations has flooded and is off the air. She can hear tornadoes, spun off by the hurricane. She reports that reservoirs upstream are being opened, worsening the flooding, yes, but the alternative is a dam breach, which would be worse. She says she’s ok. Her house is not flooding, though those of some of her neighbors are. She posts cell phone video and drone video from friends showing expanses of fast, brown water.

For my non-Houston friends- to help you understand the devastation:
Houston is huge. The greater metropolitan area is circled by the Grand Parkway – which is 170 miles long. That makes the area of the circle inside the Grand Parkway over 2200 sq. miles.
2200 square miles of densely habited, urban and suburban, areas is flooded.
Imagine if the entire state of Delaware, with twice the population of Manhattan, was under water.
That’s Houston.
It’s still raining.

August 27, 10:42 PM

Reporting from Houston, Tx-The love between neighbors here is stronger than the rain, no matter what race, faith, or political party #Harvey

August 28th, 1:00 PM

A few minutes ago, I learned that of those reservoirs–the ones that began releasing water to avoid an uncontrolled flood–one has been over-topped anyway. The other may soon follow. The Houston area has received over half its typical yearly allotment of rain in the past four days alone.

The storm is heading back out to sea, where it will strengthen, before making landfall a second time, probably in Louisiana. But it’s also possible it could hit Houston twice.

An Unprecedented Storm

As is often true of big disasters, this one owes itself to multiple factors. One, obviously, is the storm itself is unusual. Not only did Harvey grow very quickly into a very powerful storm (Category 4), it then stalled right over Houston for several days, dropping all of its water in the same place, rather than over an extended track, as most storms do. This is not the first time a storm has done such a thing, but the amount of rain is literally without historical precedent. The National Weather Service frankly admitted it has no idea what the impacts are going to be and has even had to create new colors for its weather maps in order to represent the scale of this storm. This returning to sea for more energy thing is also highly unusual.

The other part of the problem–and here I’m drawing on information from Bridgette–is that Houston is prone to flooding anyway. The soil is clay-based and does not drain well, and a development boom has dramatically worsened matters by paving over a lot of ground. There is no way for most of that water to go anywhere, except by flowing down streets and through buildings. Flooding is common in parts of the city even in ordinary rainstorms. For an extraordinary rainstorm to occur here cannot help but have catastrophic results.

What the long-term results will be are not clear, yet. An online search for “economic impact of Harvey” yields varied results–that recovery will take years, that it will be quick, that economic impacts will be large and widespread, that they will be minimal. No one really knows. The storm isn’t even over.

But two facts are worth noting.

One is that Bridgette is right; Houston, with the assistance of the rest of the nation (and even other countries–reportedly, Mexico is mobilizing to help, as it did following Katrina) is stronger than Harvey, and will survive. One of the advantages of being a very rich nation is that we can sustain billions of dollars of damage and simply pay for it. There may be bureaucratic or political hang-ups, we don’t know yet, and the physical acts of clean-up and rebuilding will take time, but we can do this.

The other thing to keep in mind, though, is that we’re not just looking at paying for clean-up and repair. Houston is the fifth-largest economy in the US, and it’s taking the better part of a week off. Zero output. None. Bad news. Houston is also the home of much of American oil refining. Right now, some refineries are closed because workers can’t drive in to work, there is no damage (or hadn’t been, as of yesterday evening) but that could change. There are other Houston-based businesses taking a hit, too, such as Sysco, the company that produces supplies for virtually every restaurant you’ve ever set foot in (seriously, look at restaurant water pitchers–they’re all exactly the same because they come from the same place). The United States as a whole is not in danger, we will get through this, but Harvey is not a local problem. It’s national, possibly global.

The one thing the flooding in Houston is not is the fault of local officials for not evacuating everybody. Bridgette, again:

We have learned from the many storms that there is a way to evacuate. The process is that the lower lying areas or those that are first in harm’s way must be the priority. If everyone from Houston got on the freeways and evacuated, then those in real trouble could not get out. An example was the horrific Hurrican Rita evacuation in 2005. Rita was just weeks after Katrina. And Rita was going to be stronger than Katrina. We were all a little shell shocked down here. During Hurricane Rita, people panicked and according to Wiki “An estimated 2.5 – 3.7 million people fled before Rita’s landfall, making it one of the largest evacuations in United States’ history.”

I was here. I stayed. Here is what happened. It was wall to wall cars. No one could move. It was hot, and gas ran out in the cars on the road. No one could get gas in to help the stranded. I fielded phone calls from friends who were caught in traffic for hours. Many finally turned around, but that was impossible because the city then opened the southbound to go north. It was excruciatingly hot and dangerous. I see the reports say that 90-118 people died even before the storm. A bus of elderly started on fire, and all were killed. These same roads and feeder roads that people traveled on are now under water in this storm. Evacuation of so many people is impossible. And, remember no one could understand how the other factors would play in this storm [unprecedented rain, recent development boom]. The weather men do an excellent job of predicting, but they can’t be sure. People prepared the best they could. Some did bug out.

I’m proud of how those in authority handled and are handling things, and I’m here. I can tell you now, after living through Allison, Houston has a long row to hoe, and at this writing, until mean big brother Harvey decides to quit picking on us and go away, we won’t know how bad things will be. We will recover because Houston is stronger than Harvey, but one thing is sure, in my book, this is no one’s fault.

August 29, 1:00 AM [emphasis mine]

So far, the confirmed death toll from Harvey is just 14 people. If Rita is any indication as to what a full evacuation would have looked like, and given that the roads where those traffic jams occurred have flooded, the decision not to evacuate any but those at highest risk may have saved thousands of lives.

Climate Change

A storm like Harvey could have happened before anthropogenic climate change. We have no record of such a thing, but perhaps one occurred before or record began. But there are several factors which make a Harvey-type storm more likely than before we monkeyed with the climate.

First, the Gulf of Mexico is warmer now, which makes deep pools of very warm water in the Gulf much more likely. When a hurricane moves across such  pool, it can intensify suddenly–which is exactly what Harvey did. It’s also what both Katrina and Rita did, as each grew dramatically in much the same way.

Second, the air is warmer now, and warmer air carries more moisture, which means more rain. In hurricanes, it’s the wind that gets the press–we rate hurricane intensity by wind speed–but it’s the water that causes the damage. Many storms, notably Irene, a few years ago, cause their most severe damage after being downgraded out of hurricane status, simply by raining a lot. Harvey is another in this pattern.

Third, the reason Harvey parked itself right over Houston for so long is that it was trapped between two high pressure zones. This scenario ought to sound familiar, because persistent high pressure zones have been involved in almost every severe weather story I’ve covered for years, now. Droughts, heat waves, snow storms, extra-tropical rainstorms, and hurricanes have all made the transition from bad weather to unprecedented disaster, in part, because they stayed in the same place longer than normal–because of persistent blocking highs. And while it hasn’t been confirmed yet, the changes in the jet stream that create persistent blocking highs (and misplaced polar vortexes and weird, hurricane-like winter storms) may be being caused by melting of the sea ice in the arctic.

One final thing to consider; yes, we are stronger than Harvey. We were stronger than Katrina, Irene, and Sandy. We were stronger than the California superdrought that drained a state’s reservoirs, the atmospheric river storms that filled those reservoirs up again and nearly breached the Oroville dam, the heat waves that grounded airplanes in Phoenix two years running, shockingly intense wildfires, and the floods in Baton Rouge that acted like a hurricane but weren’t. But how much longer are we going to keep our strength up as these things become more likely and occur more often?

Can’t we just bite the bullet and stop warming the atmosphere?


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How Heat Hurts

I got heat exhaustion today. Unfortunately, this is not an unusual occurrence for me–I seem to be unusually susceptible. I don’t know why. Heat exhaustion is one of several types of heat-related illnesses. It is not, in itself, normally dangerous, but can progress to heat stroke, which can kill you.

Heat is a matter of weather—but it is also a matter of climate. Obviously, global warming means more hot days, but the increase doesn’t work quite the way intuition says it should. Intuitively, an average warming of, say, one degree Fahrenheit, should add one degree on to typical daily temps. So if your normal summer day was 90 degrees, now it’s 91 degrees. Not a big difference. But that’s not how it works.

As I have addressed before, a small increase in average temperature results in a large increase in the frequency of heat waves. This is because there is a well-established link between rarity and severity across many different types of variation, from body height to intelligence to air temperature. A slight increase above average (a few degrees, a few inches….) translates into a dramatic decrease in frequency of occurrence. How often do you see people who are six feet tall? Now often do you see people who are seven feet tall? The difference seems larger than what a mere twelve inches would imply.

A hotter normal means that severe heat waves that used to be very rare become common-place, while the human vulnerability to heat injury remains roughly the same.

My illness today is not particularly a climate change story–it was not one of those events that make it obvious normal has changed. Hot days in mid-June are not new for Maryland. But the experience did inspire me to do some reading about how heat stroke actually works—more people die from heat than from all other natural disasters combined. I decided I wanted to know more about what happens in the body when it gets hot.

Please note that I’m skipping over issues like how to recognize and treat heat-related problems. For that information, look up a public health website maintained by a reputable medical institution (anything else, and you’ll likely be reading content written by free-lance writers who don’t know anything more about medicine than you do).

Definitions

When I received emergency medical training years ago, I learned that heat exhaustion is essentially a form of aggravated dehydration—the body is not hotter than it should be, but keeping cool is taking too much effort, including loss of so much water through sweat that blood volume drops. The symptoms are mostly the body’s attempt to compensate for lost blood volume in order to keep adequate blood flow to the brain. Heat injury and then heat stroke, in contrast, result when the body’s cooling system fails (sometimes because dehydration has become critical and the sweat response shuts off—when a person who should be sweating isn’t, that’s a very bad sign) and body temperature rises uncontrollably. Doctors then have hours or even minutes to act before the patient literally cooks to death.

Like most simple explanations, this one is not quite right. For example, brain damage in heat stroke is not caused by the brain tissue heating up, as I’d been led to believe–instead, excessive heat causes the blood/brain barrier to become leaky, allowing substances into the brain that should not be there, and that causes damage. Heat stroke, though triggered by heat (either through passive exposure to high temperature or to excessive exercise in hot weather or under too much clothing), actual injury—and often death—is not the direct result of the body cooking. After all, cooking occurs at specific temperatures (that’s why recipes work), but the temperature at which heat injury occurs is variable. There are documented cases of people surviving core temperatures above 107 degrees Fahrenheit, but there are also many cases of people dying at much lower temperatures. The body is a complex system. Heat-related injury and death are the result of complex responses to heat, not the heat itself.

The information in this post, except where noted, is taken from a document produced–or at least presented–by the US Military (service members are at high risk for heat stroke, therefore the military is interested in the issue). The “report date” of the PDF is listed as 2012, although since it is evidently a chapter in a longer book, I don’t know if the report date is earlier or later than the copyright date of the book. I don’t know how old this information is. It’s a dense read, but I’ve attempted to summarize the main points below.

How Heat Stroke Works

Not everyone is equally vulnerable to heat stroke. There are long lists of circumstances that create higher risk, so many that it might seem everybody must belong to at lest one of them—but it’s important to note that some risk factors are a matter of choice (running marathons on hot days) and some are not (being very young, very old, already ill, or poor). There are obvious social justice issues here, as I’ve discussed before.

Interestingly, several risk factors do not involve simple vulnerability to heat (as in our marathon runner, or a home-bound elderly person without an air conditioner) but rather impairments of the body’s ability to respond. A sunburn or a heat rash can impair the body’s ability to cool itself, for example. Illness or inflammation (e.g., pneumonia) makes heat stroke more likely. Heart problems, certain medications, or low potassium or sodium levels also either make heat stroke more likely or more dangerous. These facts alone should suggest the medical complexity of the problem.

Heat stroke is also a much more drawn out process than the idea of cooking would imply. Literal cooking ceases as soon as the object being cooked cools, but heat stroke isn’t over when the victim’s core temperature is brought back to normal. If he or she lives long enough, the bodily changes initiated by the heat will continue to play out. The patient will probably run a fever (which actually helps the body heal), and may also go through periods of abnormally low body temperature.  Kidney failure will probably occur between two and 24 hours after the initial collapse. The liver will likely fail after 24 to 48 hours. Mortality rates often rise about a month after mass heat stroke events (like heat waves), after patients have been discharged. The risk of dying from cardiovascular, kidney, or liver disease can remain elevated for 30 years. There may be long-term cognitive impairment. And and since many illnesses or deaths are either never recognized as related to a patient’s heat-stroke history, or never reported as such, the true prevalence of these problems is likely much higher than the data we have indicate. There has been little research done on how these long-term problems happen, and no one really knows what to do about it yet.

The bottom line is that the number of people who die of a heat wave is much higher than the number of people who die in a heat wave.

Heat stroke is actually several processes, although the whole story is not yet clear even to scientists.

The dominant process may actually be an immune response called Systemic Inflammatory Response Syndrome (SIRS). This is the same–or at least very similar–to what happens when an infection enters the bloodstream, a condition called sepsis or, less technically, “blood poisoning.” Its symptoms include fever and a whole series of both helpful and non-so-helpful biochemical changes.

Heat-induced SIRS is actually not caused directly by heat. Instead, when the body redirects more blood flow to the skin (heat stroke victims are typically bright red), the internal organs necessarily get less. Insufficient blood flow can damage the gut lining, causing it to leak endotoxin into the blood. The endotoxin, in turn, triggers SIRS–if severe enough, the endotoxin or SIRS (I’m actually not clear which–it looks as though scientists might not be sure, either), destroys the major vital organs, causing death.

Injection of endotoxin alone (into animals) triggers the clinical symptoms of heat stroke.

Another important process is DIC, which stands for Disseminated Introvascular Coagulation. Essentially, the blood starts clumping up, leaving the blood remaining in circulation way too thin. DIC can be caused either by tissue damage (sepsis is listed as a common cause, suggesting that DIC can be caused by SIRS–the immune response I just described–although that is not clear to me from the article) or by direct heat injury to the vascular system.  Besides the real risk of bleeding to death, DIC also causes, or helps cause other problems associated with heat stroke.

DIC can cause kidney failure, for example. But kidney failure can the proteins released by muscles damaged by SIRS, or by heat toxicity itself.  It can be difficult to tell which problems are causes and which are results.

Heat stress is one of several possible triggers for the release of cytokines, a class of messenger proteins that in some circumstances are a necessary part of healing–but experimental injection of these proteins triggers heat stroke symptoms including excessive body heat. In other words, the body doesn’t just get sick because it gets too hot—it also gets hot because it’s sick. Exactly what role cytokines play in actual heat stroke isn’t known, yet, but cytokines are involved in many of the processes and subprocesses of heat stroke.

There are several possible treatments for heat stroke being developed based on this more detailed understanding of the malady, but so far, heat stroke is much easier to prevent than to treat. Prevention consists not just of staying cool, but also in becoming adequately acclimatized–general good health and fitness, plus a recent history of being uncomfortably but not dangerously hot fairly often dramatically increase the body’s ability to safely withstand heat. In other words, HAVING a working air conditioner can save your life, but using it often (hiding from summer heat) puts you more at risk for those times when you do have to get by without it–if, for example, there is a power outage during a heat wave.

So?

All of this might sound like unrepentant geeking out on my part. I am, in fact, an unrepentant geek, but my primary motivation for this post is, as I said, to take a close look at a malady likely to become ever more familiar, both to us individually and as a matter of public health policy.

One study that looked at the UK has predicted that, as a result of global warming, the incidence of death from heat stroke in that country will double by 2050. That’s only just over thirty years away.

 

 

 


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Seeing Patterns

Last week, I had the distinct pleasure of a hike on Mount Desert Island with my friend and teacher, Tom Wessels–the same man who lead the hike in the White Mountains described in my post, The Ghost of White Birches. Only, then he was leading an organized group activity associated with the school I’d just graduated. This time, for the first time, we were just friends going hiking together.

Myself, my husband, our elderly but still spry dogs, and him.

Switching contexts can have an unpredictable effect on relationships, and I can be slow on the uptake when the rules change. I had left it to Tom to suggest a hike, rather than saying so myself, because I did not want him to think I was expecting him to work on his day off. But as it happened, I need not have worried. Nothing had really changed between us. And while he had no planned lectures, no educational objectives, and had not previously hiked our whole route (as a professor, he appears to meticulously plan everything), he still kept us appraised of the cultural and natural history around us, knowing and sharing our interest. Tom is not one of those people who wears radically different hats for changing circumstance. He is always and exactly himself.

He told us that part of the trail we followed ran along the bed of the first road on the island. He pointed out a big-toothed aspen so furrowed with age that it looked like an ancient cottonwood, and how two other trees of the same size and species nearby must be much younger, having smoother bark.* He commented that the rhodora was coming into bloom. He answered questions, asked and unasked.

“Sap,” he said, spotting me examining a mass of white stuff at the base of a tree. I had thought it was either sap or bird urine and that either way it indicated some story. “These spruces are not doing well. Fungus comes in, then ants, then woodpeckers. Carpenter ants can’t excavate healthy wood.” The sap had flowed from the work of a pileated woodpecker, going after carpenter ants.

I knew from previous conversations that one of the reasons the spruces are becoming more vulnerable is climate change.

Much of Mount Desert Island is dominated by spruces, a cold-tolerant genus of tree that is rare at this latitude. The island–and the coast of Maine generally–is different because the frigid Humbolt Current bathes the land in cool sea breezes and cold sea fogs. According to rangers at Acadia National Park, which includes much of the island, the Gulf of Maine is now warming faster than almost any other water body in the world. Lobsters are moving north, to the detriment of lobstermen in southern New England. Southern fish species are moving in. In warm years, every puffin chick in the state starves to death, unable to swallow the larger, southern fish their parents bring.

I was right to think the white stuff at the base of the tree held a story.

Tom sees patterns. In a somewhat different and still less-developed way, so do I. A hiker without this kind of knowledge would see a pristine wilderness, protected in perpetuity by the US Park Service. Tom sees spruces not doing well (and paper birches dying off, lobsters moving, puffins starving) and is saddened.

There is a certain comfort to be had by sharing your reality with another. We chat about our home, mine and my husband’s, in Maryland, and how our forested lot prevents our having a garden, or a solar panel, or a wind turbine, but does protect us from the damaging effects of winds. In the ten years I’ve been there, I say, we’ve survived two hurricanes (Sandy and Irene) and a derecho, and the wind mostly flows over the tops of the trees.

“Those will happen more frequently, because of climate change,” comments Tom. We know. My husband talks about the changes he’s seen in Assateague Island in the forty years he’s been watching the place. Casual visitors don’t see that, either, only an unspoiled, wild beach, but we have friends who were married in a house on that beach and the house is not there anymore. The place where it stood is now several yards off shore. Maryland is slowly sinking, a natural subsidence triggered by the retreat of the glaciers tens of thousands of years ago, but sea level rise from climate change is real, too.

Last month, in St. Michaels, a town on the Chesapeake Bay, I saw water quietly lapping over the edge of the town dock, standing a few inches deep on pavement. Nobody else said anything. Nobody acknowledged it was happening, let alone extraordinary. Tidal height can vary. There is the influence of the moon’s phase, of course, since full moons and new moons produce extreme tides, and an onshore wind can pile up water on the coast. If both occur at the same time, tides can become extraordinary quite naturally.

But the town dock would not have been built where it was if flooding were normal at the time of its construction.

Last night I dreamed that nothing I did turned out right, that I was driving down winding country roads, lost, that the roads became dangerously, fantastically steep so I pulled over, only to watch my parked car roll down hill into the back of another. The metaphor of my subconscious is clear; I don’t know what to do about any of these patterns.

My mother and I discuss politics over breakfast. We are both worried about the survival of democracy. I go to bed with a hard knot of anxiety, the same nauseous fear that has plagued me since the election. I attend marches, write political letters, sign petitions, keep this blog, but there is something else that must be done, some stronger, more effective way to fight, but through the fog of anxiety, I don’t see it. Other than to acknowledge the truth, share my reality, I don’t know what to do.

 

  • The rate at which wood grows varies, as many people know, but the bark of each species grows at a nearly constant rate. Thus, an individual growing more slowly than normal for its species will have thicker, more textured bark. With some few exceptions, trunk size plus bark texture gives a better indication of tree age than either does alone.

 


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Same March, Different Day

I’m sorry I didn’t post last week. I don’t know why I didn’t—it seemed as though I did not have time, but I don’t think that’s exactly true. I didn’t have all that much to do. More likely, the things I was doing took much longer than normal and took more energy than normal because I was anxious about something. What was I anxious about? I’m not sure. It is the nature of my particular version of anxiety to hide its source—but the fact that I just had my third nightmare about Donald Trump trying to kill me is probably relevant.

Seriously, what is with my subconscious? And is anyone else getting this? I hardly ever have nightmares about anything, and I’ve never before had nightmares about any public figure, no matter how much I might have disagreed with what they were doing. I didn’t have bad dreams about Osama bin Ladin, although I’ve heard that pretty much everyone else did. And three times now, my brain has sent me horror shows about this orange businessman.

Anxiety is counterproductive. Makes it hard to focus on anything constructive, including constructive responses to whatever is causing the anxiety in the first place. Is this why the opposition has not yet really gotten its act together? Are we all just insanely frightened by this guy?

In any case, I wanted to talk about the People’s Climate March at the end of April. I attended the one in Washington DC, so two trips to DC in eight days. At least this time I wasn’t cold.

My husband and I and almost forty others took a chartered bus up to the edge of the city, then we all took the Metro in (that’s that subway, for those not in the know). My husband had volunteered to be the bus captain, meaning he had to help shepherd everybody along, and couldn’t go with me to try to find a friend of mine who was also at the march, embedded within a different group.

I was irritated by this limitation, I will admit—I didn’t understand why our group needed a bus captain to begin with, and it was too hot, there weren’t any toilets, and nobody was listening to me. Eventually we met a collaborator in a small park who had brought a fifteen-foot-tall great blue heron puppet for us to carry and I realized two things: first, the puppet explained the need for a bus captain (a core group of us needed to stay together to work the puppet) and, second, that puppet would be visible from anywhere, meaning I could go look for my friend and be somewhat assured of locating my husband again afterwards.

I never did find my friend—I tried calling him by cell phone but we couldn’t hear each other over the crowd noise, and as a needle he happened to be marching in a very big haystack—but I did get to wander through much more of the crowd than I would have otherwise.

The day was sunny and very hot, more typical of late June than April, and the vast, assembling crowd felt rather more like a festival than anything else. A drum beat from somewhere. Bagpipers and other musicians were audible in passing. Families relaxed in the shade of trees near food trucks, and small-time entrepreneurs hawked t-shirts, other memorabilia, and bottled water. Banners and various giant puppets waved in the breeze. Some of the signs I saw were clearly left over from the science march the week before, but most were the standard fair I’d seen at every other climate-related march I’ve been to over the past few years. The water in one of my bottles tasted funny, and when I drank too much from the other I felt nauseous.  How was I going to stay cool? I’m prone to heat exhaustion, so I baled water onto my head from the reflecting pool with my hat.

I knew I was upstream, as it were, of my husband. To find him I had simply to walk in the same direction the march was going, but faster. I hurried along the sidewalk in places, weaved and bobbed through the middle of the crowd in others. I passed marching bands, more giant puppets, men dressed as Uncle Sam on eight-foot stilts. We followed essentially the same route as the climate march had, but in the other direction, beginning near the Capitol Building and ending near the Washington Monument. At one point, I came across a large group of people chanting Shame! Shame! And wagging their fingers in the air. Why? Nobody knew.

“We are shaming that building,” explained one woman, shrugged, and returned to shouting Shame!

“Isn’t that the Trump Hotel?” someone else guessed, and indeed, once we’d come up even with in, we could see that it was.

“I wonder what it’s like to be in that hotel right now?” I asked.

“Probably pretty embarrassing,” suggested someone near me.

I saw anti-fascist groups holding their own rallies in the middle of our march, as I’d seen the previous week, and once again I walked through the middle of opposing chants on the issue of abortion. Then, I’d thought that I was seeing a pro-choice inclusion within our march, attended by a counter-rally. This time I concluded—and I’m guessing this was the truth of the matter before, too—that there was a pro-life rally embedded within us and that when other marchers came near the rally they simply chanted responses, “my body, my choice!”

Eventually, I spotted the giant blue heron and rejoined my husband. I took a turn carrying part of the puppet, but the thing was unwieldy, and the extra effort set my pulse to pounding in my reddened face. I passed the huge bird wing off as soon as I could. Some of the faces in the crowd around me had gone red and blotchy, too. Ambulances weaved through the crowd along cross streets. We checked up on each other and I wondered if I could make it to the end of the route before I got sick. Gradually, more and more people were dropping out, lining the streets under shade trees, cheering and chanting and waving signs at the hardy few who kept walking.

I made it. Along the edge of the Washington Monument grounds stood long rows of portable toilets under shade trees. There was no definitive end to the march, but as we passed along those rows more and more people dropped out, slipping between the toilets out to the waiting grass, and we followed, crashing out in the shade. Crowds moved across the grounds, continuing the festival, an unstructured, apparently spontaneous rally. A kite flew high, carrying something hundreds of feet into the air—a camera. Eventually, we made our way back to our bus, all of us dazed and quiet from the heat. The driver earned a hefty tip for having fixed the air conditioning while we were gone.

Alright, interesting experience, but what did it mean?

At least 200, 000 people showed up, so I’ve heard. Aerial photographs—from the kite, I assume, as there were no helicopter flyovers, and no visible drones—show a sea of people filling the streets for blocks, our region of blue t-shirts and blue heron puppet right in the middle. It would be tempting to be reassured by such a large outpouring of pro-climate enthusiasm, but as I’ve said, the primary purpose of political demonstrations (aside from networking opportunities and a boost to the marchers’ morale) is to show elected leaders where the political wind is headed—listen to us, or we’ll vote you out! But, in point of fact, the votes have not been forthcoming. Climate denial works better than climate bravery for ambitious politicians, and nobody gets to hear much from the other kind. So, why should anyone listen to us now?

I’m not saying not to march, I’m saying we need to do something in addition to marching, and we need to do it quickly and in a very organized way.

There are also indications of a hidden ugliness to the event. Afterwards, I heard from other activists—people of color—who had been on the march, too, and were harassed repeatedly by both fellow marchers and organizers. One reported seeing an organizer insist that a certain chant stop. Why? The chant was in Spanish. I had seen nothing of the kind, but then, I wouldn’t. I’m white, and one of the most fundamental, and most pernicious, racial privileges is that if you’re white, you don’t see racism. It is therefore incumbent upon white people to seek out the perspectives of non-white people, and to believe them. I had noticed that the crowd was almost entirely white, as are many gatherings of environmentalists, and I had wondered why. Now I know.

People—specifically, white people—we have no time for that kind of garbage. Cut it out. Get it together. Now.

I’ve said that the science march was strikingly different from the series of climate marches I’ve been on, and that this one was largely a return to recent tradition. And that is true, in some ways, but not in others. Yes, there were the familiar chants (“This is what democracy looks like!”), the familiar signs, the same-old goofy, pep-rallyish mood. And yet, something was different.

There was an anger, an aggression, I had not seen before. Some of the signs were very much to the point, the point being that climate change continued means death, destruction, and pain. One showed a cartoon horrorscape of flames and cut stumps and poison smoke with the caption “Baron’s Inheritance.” Towards the end, organizers asked us to sit down, backs toward the White House, for a moment of silence—and then to get up, turn towards the White House, and produce a moment of noise. At that moment of noise, a woman beside me displayed both middle fingers and screamed “F___ YOU, YOU CORPORATE BASTARDS!!!”

I doubt she is alone in her sentiment.

Beneath the festive mood, the silly costumes, the giant puppets, there was an absence of playfulness, a presence of anger and fear. The pep rally didn’t quite work, not for me, anyway, even though that aspect of such proceedings has worked for me in the past, despite my rationalist intentions, despite my worry, even despite my occasional cynicism. It just wasn’t like this, last time I did one of these marches.

Last time, there wasn’t a climate denier in the White House.