kottke.org posts about global warming
Scientists at Oak Ridge National Laboratory have stumbled upon a process that uses “nanospikes” to turn carbon dioxide into ethanol, a common fuel.
This process has several advantages when compared to other methods of converting CO2 into fuel. The reaction uses common materials like copper and carbon, and it converts the CO2 into ethanol, which is already widely used as a fuel.
Perhaps most importantly, it works at room temperature, which means that it can be started and stopped easily and with little energy cost. This means that this conversion process could be used as temporary energy storage during a lull in renewable energy generation, smoothing out fluctuations in a renewable energy grid.
This sounds like a big deal…is it now possible to limit the effects of climate change by sinking carbon while also placing less dependence on fossil fuels? Here’s the Oak Ridge press release. That this news is almost a week old already and we haven’t heard more about it makes me a bit skeptical as to the true importance of it. (Of course, CRISPR is potentially a massive deal and we don’t hear about it nearly enough so…)
Update: A relevant series of tweets from Eric Hittinger on “why creating ethanol from CO2 cannot solve our energy or climate problems”. Wasn’t fully awake when I posted this apparently because, yeah, duh. (via @leejlh)
From XKCD, a typically fine illustration of climate change since the last ice age ~20,000 years ago.
When people say “the climate has changed before”, these are the kinds of changes they’re talking about.
And then in the alt text on the image:
[After setting your car on fire] Listen, your car’s temperature has changed before.
The chart is a perfect use of scale to illustrate a point about what the data actually shows. Tufte would be proud.
Update: Tufte is proud. (via @pixelcult)
In today’s installment of terrifying graphics about climate change, the NY Times made a series of three maps showing the potential rise of 100 degree temperatures across the United States if current greenhouse gas emission trends continue through the end of this century. Look at the areas in orange and red on the 1991-2010 map: what sort of landscape do you picture? Keeping that landscape picture in your mind, look at the orange and red areas on the 2060 and 2100 maps. Yep! And Phoenix with 163 days above 100 degrees — that’s every day from March 25th to September 4th over 100 degrees.
P.S. A word about climate change and rising temperatures. The temperature that climate scientists typically reference and care about with regard to climate change is “the average global temperature across land and ocean surface areas”. According to the NOAA, the average temperature of the Earth in the 20th century was 13.9°C (57.0°F). In 2015, the average global temperature was 0.90°C (1.62°F) above that.
In order to avoid dangerous effects of climate change, climate scientists advocate keeping the global average temperature increase below 2 degrees (and more recently, below 1.5 degrees). In late 2015, 195 nations came together in Paris and agreed to:
[Hold] the increase in the global average temperature to well below 2°C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5°C above pre-industrial levels, recognizing that this would significantly reduce the risks and impacts of climate change
That’s degrees Celsius, not Fahrenheit. I don’t know about you, but as an American, when I hear 2 degrees, I think, oh, that’s not bad. But 2°C is an increase of 3.6°F, which does seem significant.
Note also that it specifies keeping the temperature “below pre-industrial levels” and not below 20th century levels. It is maddeningly difficult to track down an exact figure for the pre-industrial global temperature, partially because of a lack of precise data, partially because of politics, and partially because of the impenetrability of scientific writing. From a piece Eric Holthaus wrote for FiveThirtyEight earlier this year:
It sounds easy enough to measure global warming: see how hot it was, compare it to how hot it used to be. But climate scientists have several ways of measuring how hot it used to be. NASA’s base period, as I mentioned above, is an average of 1951-80 global temperatures, mostly because that was the most recently available 30-year period when the data set was first created. By chance, it’s also pretty representative of the world’s 20th-century climate and can help us understand how much warmer the world has become while many of us have been alive.
Other organizations go further back. The Intergovernmental Panel on Climate Change, the body of climate scientists that was formed to provide assessments to the United Nations, bases its temperature calculations on an 1850-1900 global average. There was about 0.4 degrees of warming between that time period and the NASA base period.
Climate scientists often refer to that 1850-1900 timespan as “pre-industrial” because we don’t have comprehensive temperature data from the 1700s. But meteorologist Michael Mann, director of Penn State University’s Earth System Science Center, has argued that an additional 0.25 degrees of warming occurred between the start of the Industrial Revolution (around 1750) and 1850. Including Mann’s adjustment would bring February 2016 global temperatures at or very near 2 degrees above the “pre-industrial” average.
I now completely understand why some people deny that anthropogenic climate change is happening. Seriously. I looked for more than 30 minutes for a report or scientific paper that stated the average global temperature for 1850-1900 and I couldn’t find one. I looked at UN reports, NASA reports, reports from the UK: nothing. There were tons of references to temperatures relative to the 1850-1900 baseline, but no absolute temperatures were given. Now, I don’t mean to get all Feynman here, but this is bullshit. When the world got together in Paris and talked about a 1.5 degree increase, was everyone even talking about the same thing? You might begin to wonder what the scientists are hiding with their obfuscation.
Anyway, the important point is that according to climate scientists, we are already flirting with 1.5°C of global warming since pre-industrial times. Which means that without action, the spread of those Phoenician temperatures across the circa-2100 United States is a thing that’s going to happen.
A Siberian heatwave has led to permafrost thaws that have released long-dormant anthrax bacteria, resulting in the hospitalization of 13 people and the death of over 1500 reindeer.
Citing earlier work from 2007, they estimated anthrax spores remain viable in the permafrost for 105 years. Buried deeper, the bacteria may be able to hibernate for even longer. At the same time, where meteorological data were available they indicate temperatures in Yakutia are increasing.
“As a consequence of permafrost melting, the vectors of deadly infections of the 18th and 19th centuries may come back,” the scientists warned, “especially near the cemeteries where the victims of these infections were buried.” Cattle grave sites should be monitored, they concluded, and “public health authorities should maintain permanent alertness.”
Another one of those delightful little climate change gotchas, like the near-death of the Great Barrier Reef.
Update: Eric Holthaus talked to some experts and climatologists and yes, pathogens released by warming are something we were warned about and we need to be concerned about it.
Romanovsky says the possibility that additional pathogens may be released from the permafrost, if that is indeed the source, makes it even more important to study this specific outbreak closely. Once in the water supply, in theory, a future pathogen could spread outside the local area, carried by people or by migrating birds or animals.
Though the current outbreak is happening during an unusual period of extreme warmth, Romanovsky says that, “if it gets warmer in the future, and it seems like it will, the thawing permafrost could be massive.” A further degradation of the permafrost would allow more opportunity for the emergence of sequestered microbes.
Eric Holthaus, the internet’s favorite meteorologist, is hosting a new podcast on climate change called Warm Regards (on iTunes). A recent episode is embedded above and here’s a bit more about the show, including some info about his co-hosts:
Joining me with co-hosts Andy Revkin, a veteran environment writer for the New York Times who has covered climate change for 30 years, and Jacquelyn Gill, a paleoecologist at the University of Maine who is an actual, real-life climate scientist and flawlessly navigates climate Twitter.
Also, Holthaus recently started a project on Patreon to support his independent journalism on climate change. I’m in for $3/mo…chip in if you enjoy Eric’s work and Twitter contributions and wish to see more.1
The Industrial Revolution began in the mid-18th century in Great Britain. To provide power for the wondrous new inventions producing marvelous new goods and services, coal (and later oil) was dug out of the ground and burned, releasing billions and billions of tons of carbon dioxide. In time, the speedy introduction of all this new carbon into the atmosphere caused the Earth’s climate to change.
In order to procure new resources for manufacturing and gain access to new markets for finished goods, the British Empire expanded across the globe. At some point, Great Britain invaded nearly 90% of the world’s countries. The expansion fueled climate change and created avenues for immigration to Britain from their colonies. Their activities eventually bring them to the Middle East in search of oil.
Fast forward to 2006. Drought exacerbated by climate change is one of many factors that pushed Syria into a prolonged civil war. The war triggered a humanitarian crisis and millions flee the country, becoming refugees, and some are able to migrate to Europe and other countries around the world, including Britain. The Syrian immigration issue fueled British nationalism, racism, and xenophobia, triggering a vote about whether Britain should leave the European Union. Yesterday, more than 17 million Britons voted to leave, with strong support for Leave in areas with now-empty coalfields and declining industrialization.
Coincidence? Not even close. More than 250 years on, Britain is still dealing with the effects of the Industrial Revolution. (via @EricHolthaus, @johnupton, @MichaelEMann, @chucktodd)
Fake trees to pull carbon dioxide out of the air, sun shields to deflect heat and radiation without damaging the atmosphere, giant ice cubes mined from comets to cool down the oceans. Okay, that last one is from a Futurama episode. But some researchers really do think we can try to slow or reverse climate change with technology built for that purpose — and that we’ve already changed the Earth’s environment so much that we may have no choice. I guess it’s worth a try.
Jimmy Kimmel had some scientists on his show recently to tell the American public that anthropogenic climate change is real, that’s it’s not a prank, and that the scientific community is “not fucking with you” about this. Trigger warning: the first minute of this video features Sarah Palin speaking.
This video from Vox makes an often overlooked point about climate change. Climate change is not about saving the planet. Earth will be fine. Life, in general, will be fine. But many species of plants and animals will die. Addressing climate change is about saving plants and animals that are in some way “useful” to us and preventing human suffering. (via @mims)
Update: George Carlin riffs on this point in an old standup routine:
There is nothing wrong with the planet. The planet is fine. The people are fucked.
In the past two weeks, the results of three surveys and studies about the Earth’s climate have been released: a paper on a possible dramatic climate shift, a survey of coral bleaching at the Great Barrier Reef, and a study on the West Antarctic ice sheet. All three investigations tell the story of climate change happening quicker than was previously anticipated.
From the paper published last week by former NASA climate scientist James Hansen and a number of colleagues:
Virtually all climate scientists agree with Dr. Hansen and his co-authors that society is not moving fast enough to reduce emissions of greenhouse gases, posing grave risks. The basic claim of the paper is that by burning fossil fuels at a prodigious pace and pouring heat-trapping gases into the atmosphere, humanity is about to provoke an abrupt climate shift.
In Australia, more than 40% of the Great Barrier Reef has been damaged by coral bleaching.
Scientists who have dedicated their careers to studying the reef and its ecosystem say the current bleaching is unprecedented, and perhaps unrecoverable. The emotion in their responses so far have been palpable.
“I witnessed a sight underwater that no marine biologist, and no person with a love and appreciation for the natural world for that matter, wants to see,” said Australian coral scientist Jodie Rummer in a statement, after spending more than a month at a monitoring station in the Great Barrier Reef.
Though corals comprise only about 0.2 percent of the global oceans, they support perhaps a quarter of all marine species.
And just yesterday, a study on the West Antarctic ice sheet was released that says the ice sheet could melt much faster than previously thought, raising global sea levels by 3 feet in less than 90 years. Even the normally staid NY Times invoked the Sword of Damocles in the lede.
The great ice sheet, larger than Mexico, is thought to be potentially vulnerable to disintegration from a relatively small amount of global warming, and capable of raising the sea level by 12 feet or more should it break up. But researchers long assumed the worst effects would take hundreds — if not thousands — of years to occur.
Now, new research suggests the disaster scenario could play out much sooner.
Continued high emissions of heat-trapping gases could launch a disintegration of the ice sheet within decades, according to a study published Wednesday, heaving enough water into the ocean to raise the sea level as much as three feet by the end of this century.
Miami might not make it to the end of the century.
Oh and BTW, the maximum extent of sea ice in the Arctic was a record low in 2016, February was a total Messi-esque outlier in terms of how unusually hot it was, March, while not as warm, will still be the hottest March ever, and just look at the 2016 trend in the first chart here.
You can think of the Earth as a massive machine, with many interconnected, resilient, and redundant systems. For a long time, humans thought it was too big for our actions to affect this machine in a meaningful way. But the Industrial Revolution’s release of hundreds of millions of years of stored greenhouse gases in less than 300 years put a strain on that entire machine. We didn’t notice that strain for a long time, but we’re starting to now in the form of higher temperatures, weird weather, bleaching coral reefs, rapidly melting ice sheets in Greenland & Antarctica, and dozens of other ways. I hope there’s still time to do something meaningful about it before the slower moving parts of the machine fail permanently.
A new paper by climate scientists, including ex-NASA scientist James Hansen, warns that our climate could dramatically change within decades, not centuries.
Virtually all climate scientists agree with Dr. Hansen and his co-authors that society is not moving fast enough to reduce emissions of greenhouse gases, posing grave risks. The basic claim of the paper is that by burning fossil fuels at a prodigious pace and pouring heat-trapping gases into the atmosphere, humanity is about to provoke an abrupt climate shift.
Non-linear systems, man. Gradually, then all at once.
Update: Slate’s Eric Holthaus has more on the paper and its potential implications.
In addition to the risk of “several meters” of sea level rise this century, which Hansen calls the most important finding, the final version of Hansen’s paper gives new emphasis to the possibility that the ocean’s heat circulation system may be in the process of shutting down. The circulation shutdown would precede the rapid increase in global sea levels. If the shutdown happens, simultaneous cooling of the waters near Greenland and Antarctica and warming in the tropics and midlatitudes could spawn frequent strong storms on the order of Hurricane Sandy or worse.
If that sounds a lot like the plot of The Day After Tomorrow to you, you’re not alone.
Hansen also released a 15-minute video about the paper:
Artist Jill Pelto turns climate change graphs into art. So, for instance, a chart of rising global temperatures turns into a forest fire, which are becoming more common as temps rise:
And a graph of the retreat of glaciers over the years becomes a retreating glacier:
(via @EricHolthaus & climate central)
The forecast high temperature for Christmas Eve in New York City is 66°F. What the hell is going on? Climate change? Yes, but mostly the balmy East Coast temps are due to a super-strong El Niño.1 In the video above, Vox explains what El Niño is and how the Pacific weather pattern affects weather around the globe (including the East Coast of the US).
El Niño is a weather phenomenon that occurs irregularly in the eastern tropical Pacific every two to seven years. When the trade winds that usually blow from east to west weaken, sea surface temperatures start rising, setting off a chain of atmospheric impacts.
El Niños can be strong or weak. Strong events can temporarily disrupt weather patterns around the world, typically making certain regions wetter (Peru or California, say) and others drier (Southeast Asia). Some countries suffer major damage as a result.
A new study from scientists and economists at Stanford and Berkeley has taken a stab at determining how climate change will affect the world’s economic activity. As part of their study, they look at which countries might benefit from climate change and which might lose out. As you might expect, countries in the Northern Hemisphere with cooler climates stand to benefit while the rest of the world will not. Here are some of the projected big winners (the Nordic countries) and losers (the Middle East):
Saudi Arabia -96%
United Arab Emirates -94%
Canada (+247%) is another one of the potential big winners while the US (-36%) stands to lose out…along with all of Africa, South America, India, and China. This quote by one of the study’s lead authors, really grabbed me by the throat:
What climate change is doing is basically devaluing all the real estate south of the United States and making the whole planet less productive. Climate change is essentially a massive transfer of value from the hot parts of the world to the cooler parts of the world. This is like taking from the poor and giving to the rich.
Among other many things, anthropogenic climate change is an issue of discrimination.1 Rich, predominantly white countries caused the problem and can do the most to limit the damage, but climate change will disproportionately affect poor countries, poor people (even in rich countries), women, and people of color. The rich need to do something about it so that the poor will not suffer. The problem is, the world’s wealthy have a long history of not being incentivized to help anyone but themselves. I hope this will turn out differently…or, as sometimes happens, the desires of the wealthy and the needs of the poor dovetail into action of joint benefit.
I made a boiling frogs analogy in my post about coral bleaching this morning.
The oceans are slowly boiling and we’re the frogs who aren’t noticing.
James Fallows has been waging a small war on the use of that analogy for several years now.
You remember our old friend the boiled frog: It’s the staple of any political or business-management speech, used to show that problems that build up slowly can be explained-away or ignored, while ones that happen all of a sudden are more likely to be addressed.
Conservatives use it to talk about the expansion of the socialist state. Liberals use it to talk about climate change. Business managers use it to talk about a slide toward mediocrity. Everyone can use it to talk about something.
And that’s the problem with boiled-frogism. The minor issue is that the metaphor is flat wrong. If you put a frog in a pot of lukewarm water and gradually heat it up, the frog will stay there — until things get uncomfortably warm, at which point it will climb out. But if you drop a frog into a boil of already-boiling water, the poor creature will be so badly hurt and scalded that it will stay there and die.
I’m going to defend my usage just a little. The ocean is literally water that is getting warmer. But other than that, yeah, guilty as charged. (via @jpiz)
A persistent underwater heatwave is causing corals worldwide to bleach, and scientists believe up to 5% of the world’s coral will die permanently.
Hoegh-Guldberg said he had personally observed the first signs of bleaching on Australia’s Great Barrier Reef in the past fortnight, months before the warm season begins. He said the warming pattern indicated bleaching this summer would likely affect 50% of the reef, leaving 5-10% of corals dead. Eakin said seeing bleaching on the reef at this time of year was “disturbing”.
Also, no matter how many times I read this, it never gets less scary:
Since the early 1980s the world has lost roughly half of its coral reefs.
The oceans are slowly boiling and we’re the frogs who aren’t noticing. (via @EricHolthaus)
It’s the Pope’s first time in America and we sent him straight to Congress. That doesn’t exactly seem like we’re putting our best foot forward. In his historic speech to a joint session of Congress, Pope Francis addressed climate change, capitalism, the death penalty and immigration. MoJo pulled out the ten most important lines from the speech.
“This Pope often operates through symbolism and gestures that convey his intentions in ways that words never could.” The New Yorker on Pope Francis and his little Fiat.
With California in the midst of a particularly intense multi-year drought and 2015 looking to be the warmest year on record by a wide margin,1 Edward Burtynsky’s “Water” series of photographs is especially relevant.
Many of photos in the series are on display in Berkeley through February and are also available in book form.
Update: Burtynsky also collaborated on a documentary about water called Watermark. Here’s a trailer:
The film is available to watch on Amazon Instant and iTunes. (via @steveportigal)
In Rolling Stone, Eric Holthaus writes that as far as climate change is concerned, we are already past the point of no return. The things climate scientists have warned against are already beginning to happen…and faster than predicted.
Hansen’s new study also shows how complicated and unpredictable climate change can be. Even as global ocean temperatures rise to their highest levels in recorded history, some parts of the ocean, near where ice is melting exceptionally fast, are actually cooling, slowing ocean circulation currents and sending weather patterns into a frenzy. Sure enough, a persistently cold patch of ocean is starting to show up just south of Greenland, exactly where previous experimental predictions of a sudden surge of freshwater from melting ice expected it to be. Michael Mann, another prominent climate scientist, recently said of the unexpectedly sudden Atlantic slowdown, “This is yet another example of where observations suggest that climate model predictions may be too conservative when it comes to the pace at which certain aspects of climate change are proceeding.”
Since storm systems and jet streams in the United States and Europe partially draw their energy from the difference in ocean temperatures, the implication of one patch of ocean cooling while the rest of the ocean warms is profound. Storms will get stronger, and sea-level rise will accelerate. Scientists like Hansen only expect extreme weather to get worse in the years to come, though Mann said it was still “unclear” whether recent severe winters on the East Coast are connected to the phenomenon.
You might also like to read Adam Sobel’s reaction to this piece. As I wrote in reaction to James Hansen’s recent paper: “That’s the thing about nonlinear systems like the Earth’s climate: things happen gradually, then suddenly.”
Update: A group of climate scientists at Climate Feedback analyzed Holthaus’ piece at his request for accuracy.
While the information within the article is mostly accurate, the main issue for scientists is the article’s framing of the information. More specifically, the article implicitly attributes many weather events to human-induced climate change, while the influence of human activity on these events is not always supported by science, or is at the frontier of scientific knowledge and still debated.
James Hansen, NASA’s former top climate scientist, is joined by 16 other leading climate scientists in a paper with some alarming conclusions. The gist is that the glaciers in Antartica and Greenland are melting so much faster than previously predicted that the global sea level will rise more than 10 feet in as little as 50 years, rendering many coastal cities uninhabitable. From Eric Holthaus in Slate:
The study — written by James Hansen, NASA’s former lead climate scientist, and 16 co-authors, many of whom are considered among the top in their fields — concludes that glaciers in Greenland and Antarctica will melt 10 times faster than previous consensus estimates, resulting in sea level rise of at least 10 feet in as little as 50 years. The study, which has not yet been peer reviewed, brings new importance to a feedback loop in the ocean near Antarctica that results in cooler freshwater from melting glaciers forcing warmer, saltier water underneath the ice sheets, speeding up the melting rate. Hansen, who is known for being alarmist and also right, acknowledges that his study implies change far beyond previous consensus estimates. In a conference call with reporters, he said he hoped the new findings would be “substantially more persuasive than anything previously published.” I certainly find them to be.
That’s the thing about nonlinear systems like the Earth’s climate: things happen gradually, then suddenly. This is much more terrifying to me than the Pacific Northwest earthquake. BTW, as a reminder, here’s what NYC and the surrounding area looks like with 10 more feet of water. Goodbye JFK Airport.
Update: The paper is now available online.
Update: In the New Yorker, Elizabeth Kolbert provides a bit more explanation and context about Hansen’s paper.
What the new paper does is look back at a previous relatively warm period, known as the Eemian, or, even less melodically, as Marine Isotope Stage 5e, which took place before the last ice age, about a hundred and twenty thousand years ago. During the Eemian, average global temperatures seem to have been only about one degree Celsius above today’s, but sea levels were several metres higher. The explanation for this, the new paper suggests, is that melt from Antarctica is a non-linear process. Its rate accelerates as fresh water spills off the ice sheet, producing a sort of “lid” that keeps heat locked in the ocean and helps to melt more ice from below. From this, the authors conclude that “rapid sea level rise may begin sooner than is generally assumed,” and also that a temperature increase of two degrees Celsius would put the world well beyond “danger.”
“We conclude that the 2°C global warming ‘guardrail,’ affirmed in the Copenhagen Accord, does not provide safety, as such warming would likely yield sea level rise of several metres along with numerous other severely disruptive consequences for human society and ecosystems,” Hansen and his colleagues wrote.
Because of climate change and other activities caused by humans (invasive species, habitat loss), hybridization of species is resulting in things like super-sized coyotes, pizzly bears (grizzly/polar bear hybrids), and other animals that may not be ideally suited to survive.
Some scientists and conservationists see the coywolf as a nightmare of the Anthropocene — a poster child of mongrelization as plants and animals reshuffle in response to habitat loss, climate change and invasive species. Golden-winged warblers increasingly cross with blue-winged warblers in the U.S. Northeast and eastern Canada. Southern flying squirrels hybridize with northern flying squirrels as the southern species presses northward in Ontario. Polar bears mate with grizzlies in the Canadian Arctic along the Beaufort Sea to produce “pizzly bears.”
All of this interbreeding upsets the conventional notion of species as discrete, inviolable entities. Moreover, some scientists and conservationists warn that hybridization will degrade biodiversity as unusual species are lost to genetic homogenization.
Partly scientists fear hybrids will be less fit than organisms that have evolved in place over eons. And often that is true, but the problem solves itself over time as hybrids lose out in the competitive race for survival.
University of Minnesota student Daniel Crawford and geography professor Scott St. George have collaborated on a piece of music called Planetary Bands, Warming World. Composed for a string quartet, the piece uses climate change data to determine the musical notes — the pitch of each note is tuned to the average annual temperature, which means as the piece goes on, the musical notes get higher and higher.
Vox has a list of all the 2015 Pulitzer Prize winners. I am especially pleased to see Elizabeth Kolbert win the general nonfiction category for The Sixth Extinction: An Unnatural History…I’ve been reading her writing on climate change and environmental issues in the New Yorker for years now.
Jeffrey Linn makes maps that show how extreme sea level increase will impact major cities around the globe. Recently he made a map of NYC showing what it would look like if sea levels rose by 100 feet, which is what would happen if a third of the world’s ice sheets melted. So long, most of Manhattan and Brooklyn; hello Coral Gardens, Prospect Beach, and Sunset Island. Prints are available.
See also Linn’s maps of a drowned London, the bay of LA, and islands of Seattle.
A recent paper by three climate scientists concludes there’s a high risk of an unprecedented drought in the Southwest and Midwest United States later this century, even if we manage to get our carbon emissions under control. The scientists say it’ll be drier in the Western US than at any point in the past 1000 years.
In the Southwest and Central Plains of Western North America, climate change is expected to increase drought severity in the coming decades. These regions nevertheless experienced extended Medieval-era droughts that were more persistent than any historical event, providing crucial targets in the paleoclimate record for benchmarking the severity of future drought risks. We use an empirical drought reconstruction and three soil moisture metrics from 17 state-of-the-art general circulation models to show that these models project significantly drier conditions in the later half of the 21st century compared to the 20th century and earlier paleoclimatic intervals. This desiccation is consistent across most of the models and moisture balance variables, indicating a coherent and robust drying response to warming despite the diversity of models and metrics analyzed. Notably, future drought risk will likely exceed even the driest centuries of the Medieval Climate Anomaly (1100-1300 CE) in both moderate (RCP 4.5) and high (RCP 8.5) future emissions scenarios, leading to unprecedented drought conditions during the last millennium.
Eric Holthaus has the layperson’s explanation of the study and its implications.
Smerdon’s study is the first to examine the future risk of “megadrought” in the southwest and central United States in the context of historical episodes of drought in the same regions. Smerdon’s study suggests that the coming years are likely to see droughts worse than the epic dry periods that are thought to have caused profound changes to human settlement in the region over the last millennium.
“They’re ‘mega’ because they are droughts that lasted in these regions for multiple decades,” said Smerdon in an interview with Slate. “We haven’t seen anything like this since at least the 1400s.” In comparison, the current California drought is four years old, though drought has been present in most of the last 15 years somewhere in the West.
Update: This NASA video provides a quick overview of this study and what it means for our climate.
Brad Plumer of Vox plays around with the climate change Global Calculator and discovers, among other things, eating less beef and slowing the world’s population growth would significantly slow global warming.
The IEA scenario I started with assumed that, by mid-century, the average person will be eating 2,330 calories per day, including 220 calories of meat. It also assumes we’ll be eating more beef — that is, about 25 percent of the world’s meat will come from ruminants like cows, up from 22 percent today. Since cows produce a lot of methane, this is significant.
But what if we tweaked those assumptions? I told the calculator to assume that in 2050, the average person was only consuming 152 calories of meat per day — which is the WHO’s target for a healthy diet. I also assumed that the mix of meat stayed similar to what it was today — marginally less beef, more chicken and pork.
The result? Global greenhouse-gas emissions dropped significantly. We’re now on pace for around 2.5°C of global warming, give or take.
On the off chance you get this before it spontaneously combusts, you should probably know that Earth just experienced its hottest year on record (again). You can blame humans, you blame nature, you can blame Mister Heat Miser. But for most scientists, there is a towering body of evidence to explain this inferno, and the debate over what’s causing the warm-up has already been decided (which is good, because the venue where the debate was being held just melted).
WaPo got reactions to the latest numbers from 21 scientists: “The temperature record is yet another brick in the massive wall of evidence that the climate is warming due to human activity.” Hey, (Science) Teacher, leave them kids alone…
If we’re going down in flames, let’s at least take 5 charts that explain 2014’s record-smashing heat. Or perhaps you’d prefer an animation?
Apparently, human activity has pushed Earth beyond four of nine planetary boundaries. (In layman’s terms: Uh oh.)
In other news, ocean life faces mass extinction.
And now some potential good news about climate change. Efforts to restore the world’s rainforests have gained traction and are having small but definite effects on the amount of carbon dioxide in the atmosphere.
Over just a few decades in the mid-20th century, this small country chopped down a majority of its ancient forests. But after a huge conservation push and a wave of forest regrowth, trees now blanket more than half of Costa Rica.
Far to the south, the Amazon forest was once being quickly cleared to make way for farming, but Brazil has slowed the loss so much that it has done more than any other country to limit the emissions leading to global warming.
And on the other side of the world, in Indonesia, bold new promises have been made in the past few months to halt the rampant cutting of that country’s forests, backed by business interests with the clout to make it happen.
In the battle to limit the risks of climate change, it has been clear for decades that focusing on the world’s immense tropical forests — saving the ones that are left, and perhaps letting new ones grow — is the single most promising near-term strategy.
I wish Arbor Day was still a bigger thing. Parts of the US used to be covered by vast forests as well and an effort to encourage the planting of more trees might have an impact not only on our climate but also on the wellbeing of people. It might not seem like much in comparison to the Amazon rain forest, but planting millions of trees each year in the US, if you did it consistently over 20-25 years, would be a wonderful thing. (via @riondotnu)
Update: According to this publication by The Forest History Society, American forests are in better shape today than they’ve been in decades.
Today about one-third of the land area of the U.S. is forested. This is about two-thirds of the forest area that existed in 1600. The area of forestland today is about the same as it was in 1920.
The average volume of wood per acre in U.S. forests today is 50 percent greater than it was in 1953. In the eastern United States, average volume per acre has almost doubled since 1953.
The headline from Eric Holthaus’ latest piece is arresting: The Last Time There Was This Little Arctic Ice, Modern Humans Didn’t Exist.
Ice has been a relatively constant feature of the Arctic for most of the past 36 million years, but there have been some gaps. Scientists aren’t exactly sure what happened during the most recent major ice-free period, but it’s often considered an analog to our future, warmer Earth. The only difference is, this time, the gap in Arctic sea ice is being caused by us.
The US and China, the two largest carbon polluters in the world, have struck an accord on climate change.
As part of the agreement, Mr. Obama announced that the United States would emit 26 percent to 28 percent less carbon in 2025 than it did in 2005. That is double the pace of reduction it targeted for the period from 2005 to 2020.
China’s pledge to reach peak carbon emissions by 2030, if not sooner, is even more remarkable. To reach that goal, Mr. Xi pledged that so-called clean energy sources, like solar power and windmills, would account for 20 percent of China’s total energy production by 2030.
Here’s the official statement from the White House. The NY Times calls the agreement “ambitious” and a “landmark”, but Tyler Cowen says:
People, the China emissions “deal” isn’t much more than a press release…
But James Fallows, who has written extensively on China recently, is more positive.
The United States and China have apparently agreed to do what anyone who has thought seriously about climate has been hoping for, for years. As the No. 1 (now China) and No. 2 carbon emitters in the world, and as the No. 1 (still the U.S.) and No. 2 economies, they’ve agreed to new carbon-reduction targets that are more ambitious than most people would have expected.