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Obama Just Created a Carbon Cap-and-Trade Program
As the Obama Administration honed its historic new climate rules affecting power plants, it began thinking about electricity more broadly. It was a shift in perspective that in the end may produce the nation’s newest system for trading pollution.
Instead of looking solely at how each state could reduce pollution from its electricity sector, the U.S. Environmental Protection Agency’s new carbon dioxide limits emphasize interstate cooperation.
That cooperation will be possible, the EPA realized as it reviewed millions of public comments on the plan’s draft, partly through the regional nature of the nation’s electrical grids. The EPA’s Clean Power Plan, finalized Monday, envisions a nation in which interstate electrical grids serve as backbones for renewable energy and pollution trading and a carbon cap-and-trade program.
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States where more clean energy is being produced than is required by the Clean Power Plan could, in the coming years, sell their surplus achievements to more laggardly states. The new rules create a system in which those trades can be made without any need for special interstate agreements.
“That's great news, to put it mildly,” Environmental Defense Fund economist Gernot Wagner said. “Putting a price on carbon emissions via cap and trade is among the best possible ways to get emissions down quickly and cheaply."
Europe uses a cap-and-trade program to keep its carbon dioxide pollution within levels required by international agreements. Two cap-and trade programs also operate in the U.S., and states are considering creating more. Obama was elected to his first term vowing to introduce a cap-and-trade program to fight climate change, but he couldn’t get enough support for it from Congress.
The draft of the new rules, published a year ago, listed interstate collaboration as a possible tool for achieving compliance — an option that has interested most states. The final version promotes it. It encourages states to join an existing cap-and-trade program, or develop their own trading-based approach to pollution reductions.
“The most striking change, from what I’ve seen, is the degree to which state-level and multi-state cap-and-trade systems are now explicitly encouraged,” Harvard University environmental economics professor Robert Stavins said.
The Clean Power Plan effectively creates a new national cap-and-trade program, allowing states to trade pollution credits with each other — without setting up special interstate agreements beforehand.
States that fail to produce their own plans to comply with the Clean Power Plan may be forced by the federal government into such a program.
Under a proposal accompanying Monday’s rule, the federal government would push states “that do not submit an approvable plan” to comply with the new rules into a trading program.
“Whereas the proposed rule was virtually silent on trading, the final rule explicitly encourages it — and makes provisions for it,” Stavins said.
In last year’s draft, the EPA controversially announced that some states would be required to make much larger cuts than others. That was based on opaque calculations of states’ potentials to make such cuts. Those differences were reduced in the final rule, published Monday.
The changes will force for some states, like Wyoming and Kentucky, to be more ambitious than they previously realized. "The final rule released today is twice as bad for Kansas as the proposed rule released last summer," Kansas Gov. Sam Brownback (R) told the AP.
Dave Johnson coal-fired power plant in central Wyoming.
Credit: Greg Goebel/flickr
But it also eased demands on some states, such as California, which serves as a clean energy hub for the region. California’s own state rules to reduce greenhouse gas pollution are more stringent and far-reaching than the new federal rule.
Some of the biggest polluters, including Texas and Ohio, will be required to make the biggest reductions in pollution rates under the new rule. New Jersey, California and six smaller states will be allowed to increase the amount of pollution they produce in 2030, compared with 2012, as their populations increase.
“We have opened it up so that we can look at capacity for renewables and natural gas across the regions — a much broader area,” the EPA’s top air quality official, Janet McCabe, told reporters Monday during a phone call. “That means there’s more opportunity to shift to cleaner natural gas and renewables broadly across the sector.”
With three exceptions, all U.S. states are expected to decrease the amount of pollution they release for every megawatt-hour of electricity generated by 2030
The flip side to the EPA’s new approach is that the two states that lack grid connections with any others — Hawaii and Alaska — were placed into the EPA’s ‘too hard’ basket. They have been excluded from the final rule altogether.
“Alaska will be exempt,” Alaska Sen. Lisa Murkowski (R) told the Alaska Dispatch News on Monday, after speaking with the EPA. “This is by far the best possible outcome for our state and therefore a significant victory.”
The EPA’s McCabe, though, disagreed with that characterization. “I wouldn’t use the world exempt — I would use the word ‘defer,’ ” she told reporters.
“The Clean Power Plan, as it applies to the contiguous states, is very dependent on the interconnectedness of the grid,” McCabe said. “What we found was that we don’t feel we have the kind of data and information we need to estimate final goals for Alaska, Hawaii, Guam and Puerto Rico at this time.”
That means Alaska and Hawaii may eventually be required to comply with the rule — though McCabe said there are no timelines for that. Vermont, meanwhile, has no coal power plants, and it’s the only state in the Lower 48 that won’t be directly affected by the Clean Power Plan.
Climate Central's Alyson Kenward and Sarthak Gupta provided data analysis for this story.
All of 2015’s Rain for the U.S. in 14 Seconds
It’s no secret that it has been really wet in the Southeast and really dry out West over the first half of the year. But to really understand the split and how we got here, NASA has a helpful, color recap of the year in rain.
The imagery comes courtesy of the agency’s Global Precipitation Measurement constellation of satellites. In February last year, NASA and the Japan Aerospace Exploration Agency launched the lynchpin of the system — 12 satellites that can sense 13 different types of precipitation, including snow and light rain, the first of its kind to be able to do so from space. In the animation, green indicates lower rainfall totals while red and purple are higher totals, much like you'd expect for a radar image.
All those sensors help paint a clear picture of liquid and frozen precipitation across the U.S. Due to a series of storms in late May, Oklahoma and other parts of the Southeast racked up ridiculous rainfall totals. Those storms provided 200 to 600 percent more May rainfall than normal, set all-time monthly records, and obliterated a drought that had gripped the region for 5 years.
Another blast of rain from Tropical Storm Bill in mid-June brought rainfall totals for the year in excess of 75 inches of rain for parts of the region according to NASA. In comparison, some cities in the region usually receive just 40 inches for the whole year.
That’s the haves. Then there are the have nots. A notable lack of rainfall is the story for California for the fourth year in a row. The state continues to be mired in drought and has seen $2.7 billion agricultural losses. But it isn’t alone as Washington and Oregon have fallen into the same plight.
While it looks like parts of the Cascades have received a fair amount of precipitation, the visualization is missing one key indicator of drought: temperature. And on that front, Washington and Oregon have dealt with particularly high temps, leading to what scientists have termed a “wet drought.” This winter was dry, but not bone dry for the region. But it was the second-warmest winter on record and a good portion of precipitation fell as rain rather than snow.
The lack of snowpack left those states without a critical reserve of water through the dry summer season and led Washington Gov. Jay Inslee to issue an emergency drought declaration in May.
Both Washington and Oregon are completely in some form of drought. While they’re not suffering from as big a deficit as California’s multi-year dry spell, it’s still a cause for concern, particularly as El Niño strengthens. During El Niño years, the Pacific Northwest typically receives less precipitation than usual so another dry winter is looking more likely. That means the Global Precipitation Measurement satellites will likely have to look elsewhere for rain and snow.
Surging Renewables Frame EPA’s Historic Climate Rules
In its signature bid to reimagine America’s power infrastructure to help slow climate change, the Obama Administration has ratcheted up its demands and expectations for pollution reductions from America’s electricity sector for the years ahead.
Pointing to recent projections for rapid advances in renewable energy and energy efficiency technologies, the U.S. Environmental Protection Agency’s final version of the Clean Power Plan, which will be released and signed Monday by President Obama, sets a new, more ambitious benchmark for pollution reductions in the year 2030.
If legal challenges can be overcome, the historic rule will help spur closures at coal power plants. Those will be replaced by new energy flowing from solar panels, wind turbines and other cleaner sources, complemented by reduced demand for electricity.
Obama’s second-term efforts to slow climate change are widely opposed by Congress, so the new rule relies on an existing law — the Clean Air Act of 1970 — to force states to reduce carbon dioxide pollution from power plants.
Basic details of the finalized rule were released to reporters Sunday, showing it’s expected to contribute to a national electricity mix containing 28 percent renewable energy in 2030. When the draft plan was published a year ago, the EPA anticipated it would lead to an electricity mix containing 22 percent renewable energy by that time.
In a call with reporters Sunday, EPA Administrator Gina McCarthy said the “projection that we are seeing” from within the federal government for renewable energy growth “is much more aggressive than what we anticipated” last year. “So we have larger amounts of renewables that are anticipated to be in the energy mix, regardless of this rule.”
BREAKING: On Monday, @POTUS will release his #CleanPowerPlan—the biggest step we've ever taken to #ActOnClimate. https://t.co/BU1PF0wjUK
— The White House (@WhiteHouse) August 2, 2015
Last summer, when a draft of the rule was released, the agency proposed requiring power sector climate pollution to decline to 30 percent below 2005’s levels by 2030. After reviewing the new energy projections and more than 4 million comments regarding the draft rule, that requirement is being boosted to 32 percent.
The tightening of pollution requirements for the year 2030 comes with a tradeoff. Instead of taking effect in 2020, the rule would take force in 2022. States that begin achieving reductions ahead of 2022 could receive credits that would reduce their requirements after 2022.
The year 2005 represented a record year for the amount of greenhouse gas pollution pouring out of America’s power plants. Happenstance reductions since then mean the U.S. electricity industry appears to be nearly halfway toward meeting the EPA’s new rule — long before it even takes effect.
After 2005, a deep recession, combined with falling prices for natural gas and renewable energy and projects that reduce waste, helped curtail demand for heavily polluting coal. The Clean Power Plan aims to accelerate the trend. The U.S. Energy Information Administration reports that electricity generation produced 2,053 million metric tons of carbon dioxide pollution in 2013, which was 15 percent below the 2005 level.
The Clean Power Plan is underpinning the pledge by the U.S. to the rest of the world to ease greenhouse pollution, including from power generation, transportation and other sources, by at least 26 percent by 2025 compared with 2005 levels. That pledge was made ahead of global climate talks scheduled for Paris in December.
“The government is regulating carbon pollution from the biggest source — power plants — for the first time, and in a very substantial and serious way,” David Doniger of the Natural Resources Defense Council said Sunday. He said he was waiting to see the final rule before reaching any firm conclusions about it.
“The U.S. is the lynchpin of getting a successful global effort to curb climate change,” Doniger said. “The clean power plan is the lynchpin of the U.S. domestic program.”
As part of a public relations push ahead of the release of the new rule on Monday, Obama narrated a video describing the new rule as “the biggest, most important step we’ve ever taken to combat climate change” — something he said is making disasters “more frequent, more expensive, more dangerous.”
The White House and EPA are also promoting the public health and financial benefits of the new rule, which they say will reduce asthma rates and utility bills. Utilities and a number of states are trying to block the new rules from taking effect, arguing in court that they go further than the Clean Air Act allows.
What Changes to Expect from Obama’s Clean Power Plan
By Valerie Volcovici, Reuters
The U.S. Environmental Protection Agency will unveil as soon as Monday the final version of a sweeping - and controversial - regulation to cut carbon emissions from the electricity sector.
In its initial version, the Clean Power Plan called for cutting the country's power plant emissions 30 percent from 2005 levels by 2030, setting different targets for each state.
The proposal is the signature piece of President Barack Obama’s climate change policy. White House Chief of Staff Denis McDonough said this week that the final rule will be "stronger in many ways than the proposed rule."
President Barack Obama meets with National Security Council chief of staff Denis McDonough on Dec. 29, 2009.
Credit: The White House/flickr
But the Clean Power Plan has been sharply criticized by the energy and manufacturing industries and some energy-producing states, and opponents have already vowed to challenge the regulation in court.
The final rule is expected to accommodate some of that opposition, as well as take into account feedback from over 4.3 million public comments. Among other things: The EPA is expected to push back the rule's start date by two years to 2022, according to a slide posted by the agency briefly on its website on Tuesday.
Here are some things to look for in the final rule.
Why will the EPA push the start date back?
One of the biggest complaints about the draft proposal was the timetable. Some coal-reliant states complained that moving too quickly on building out natural gas pipelines and shutting down coal plants could lead to electricity shortages. And the Edison Electric Institute, a U.S. utility lobby group, said the interim goals would make electricity more costly for consumers. Delaying the start date and giving extra credit to states that took early action offers an "easy concession" for the EPA, according to the Resources for the Future think tank.
Will the EPA change how states can hit their targets?
The EPA set individual goals for each state to reduce the carbon intensity of their power plants based on a mix of four “building blocks”: improving efficiency of coal-fired power plants; replacing more coal with natural gas; deploying more wind, solar and hydro power and preserving nuclear power; and expanding consumer energy efficiency programs.
The agency is expected to revise some of their assumptions about how quickly states can switch out coal for natural gas, while taking into account growing penetration of renewable energy sources.
“They will be updating information on renewables and efficiency to incorporate data that wasn’t included the first time around," said David Doniger, a director at the Natural Resources Defense Council. "That really ups what you can get out of those sources."
On the other hand, South Carolina, Georgia and Tennessee hope to see less stringent targets in the final rule. Those states have nuclear plants under construction - but not yet operating. The EPA had treated those states as if the plants were already generating power, raising unrealistic expectations for the rate of cuts, those states said.
Will the EPA give states clearer ground rules on interstate emissions trading?
Many experts expect the EPA to make it easier for power plants to trade emission permits as a way to meet their carbon-reduction targets. Allowing states to measure emissions by total tonnage makes it easier for plants to “trade those tons,” said Chuck Barlow, head of regulatory affairs at Entergy, a power generator based in New Orleans. Barlow said state air regulators already trade sulfur permits this way. He also expects the EPA to facilitate that emissions trading by dropping requirements for them to strike legal agreements - some of which would require legislative approval - between states.
Will the EPA prepare a federal plan for states that "say no" to the Clean Power Plan?
Senator Mitch McConnell of Kentucky has been urging governors to ignore the EPA rule, though so far only Oklahoma has said it would not comply. The EPA is now expected to reveal a "federal implementation plan" that states would be forced to adopt if they miss a 2016 deadline for submitting plans on how they propose to meet their targets.
Reporting by Valerie Volcovici; Editing by Jonathan Oatis
What Has Changed Since Climate Talks in Copenhagen?
By Fiona Harvey, Ensia
This year will mark the most important negotiations on climate change since the 15th gathering of the Conference of the Parties to the United Nations Framework Convention on Climate Change talks in Copenhagen in 2009, COP 15. Those talks ended up with progress on several important fronts, such as getting developed and developing countries to jointly agree on emissions targets for the first time, but were marred by scenes of chaos in the final hours and bitter recriminations among governments.
President Obama briefs European leaders following a multilateral meeting at the United Nations Climate Change Conference in Copenhagen, Denmark, Dec. 18, 2009.
Credit: The White House/flickr
No one wants to repeat the experience of Copenhagen — least of all the French government, which, as host to this year’s gathering, is determined to wring commitments from governments well in advance of the start of the talks in order to be sure of getting a deal.
The world has changed markedly since 2009, with key developments in science, geopolitical shifts and a new focus on climate change that all put this year’s crunch conference in a far different context from the last one. As we prepare for COP 21, it’s worth examining some of the most important of these changes and considering how those differences might influence the tenor of the talks and, ultimately, the outcome.
First is the expansion of our scientific knowledge. Thanks to ongoing work from thousands of researchers around the world, we now know even more than we did in 2009 about the workings of climate change, its probable future impacts and what we need to do to avoid the most damaging consequences.
That is the good news. The bad news is that the warnings from leading scientists are growing ever more urgent.
Copenhagen was informed by the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, the body of the world’s leading climate scientists, which summarized the state of our knowledge at that time. The 2007 report found that global warming was occurring with a 90 percent certainty that the cause was largely our burning of fossil fuels and disruption of natural systems. It also set out predictions for future warming and its consequences. Temperatures would rise by between about 1.8°C (3.2°F) to about 4°C (7°F) by the end of the century, the scientists posited. This would take warming to more than the symbolically important 2°C (3.6°F) over preindustrial levels that scientists estimate is a probable key threshold of the climate system, beyond which aspects of climate change are likely to become catastrophic and irreversible.
The most recent IPCC report was published in three parts in 2013 and 2014, with summaries meant to help inform policy-makers. The findings strengthened the science reported in 2007, with an elevated certainty — now 95 percent — that warming has a human cause and refinements on projections for changes in sea level, ice melt, upper atmosphere warming and other parameters.
Two things stood out above the other findings: an examination of the so-called “pause” in global warming, so much talked about in recent years, and estimates of the world’s “carbon budget,” or the amount of greenhouse gas that can safely be released into the atmosphere if the 2°C limit is not to be exceeded.
On the “pause,” the IPCC warned that there was still too little data to decide the cause of the slight slowdown in the upward march of global temperatures in the past 10 to 15 years. Periods of slower rise in temperatures are to be expected because of natural variations, it noted, and there may be other causes. “Each of the last three decades has been successively warmer at the Earth’s surface than any preceding decade since 1850,” the report observed. “In the northern hemisphere, 1983 to 2012 was likely the warmest 30-year period of the last 1,400 years.” Temperature trends could only be reliably observed over periods of about 30 years, the scientists said.
The IPCC’s estimate of a carbon budget found that about half of the carbon that we can emit and stay within 2°C has already been released into the atmosphere. New science on the pause has come forward that was not in time to be included in the IPCC report. This includes studies showing that a likely cause is the increased absorption of heat by the oceans. Further studies will undoubtedly follow: This year’s temperatures are once again breaking records, indicating the pause may be ending.
The IPCC’s estimate of a carbon budget found that about half of the carbon that we can emit and stay within 2°C has already been released into the atmosphere. This is crucial because, for the first time, it gives a clear idea of what we can safely do in producing further emissions. On current trends, we would use up the remaining budget in about three decades.
In the context of the COP talks, carbon budgets are highly controversial, because they suggest that the atmosphere could be “carved up” into finite portions of carbon emissions that could be allocated to rich and poor nations. That issue is fraught with notions of equity that will be impossible to resolve before Paris, and perhaps ever. However, even if policy-makers refuse to be bound to considerations of a carbon budget, the issue — and the IPCC’s calculation — will loom over the talks.
One further note on the IPCC: The impact of the Fourth Assessment Report on the 2009 talks was marred by the “Climategate” scandal that erupted just before the summit. Hackers found emails from IPCC scientists supposedly showing them disguising key data, and quickly afterward a handful of flaws were found in the report itself. Although the errors did not have large ramifications — and, as the scientists noted, were few relative to the overall length and complexity of the report — they were damaging to the IPCC’s public image.
The IPCC has learned from this experience, and no errors have yet been reported in the latest update. It remains to be seen whether hackers and their backers have further tricks up their sleeves ahead of Paris.
Click image to enlarge
At the same time scientific warnings on the need to make urgent cuts in emissions have intensified, global emissions have continued to rise in most of the intervening years. The International Energy Agency reported a small fall in emissions from energy in 2009, after the financial crisis. Afterward, the upward trend resumed until 2013, when falling coal use in China resulted in a stalling of emissions growth. It remains to be seen whether this was a temporary blip or a more concerted “decoupling” of carbon from economic growth.
Another important emissions milestone was reached recently: China’s per capita carbon emissions exceeded those of Europe for the first time. Per capita emissions are important because many in the developing world regard them as a fairer measure than gross aggregate emissions, so for China to join the rich club in this respect marks yet further divergence of its interests from many smaller developing countries.
While emissions have risen since Copenhagen, technology has also advanced. Renewable energy sources have come down rapidly in price, to make wind and solar, at least in the most favorable cases, competitive with fossil fuel electricity generation. The widespread use of fracking in the U.S. has meant the world’s second biggest emitter is on track to reducing the intensity of its emissions from energy use. However, the rise of fracking should be viewed with caution: Poorly managed fracking facilities can leak methane, a potent greenhouse gas; and shale oil, to which many frackers are turning, is much more emissions-intensive than shale gas. Meanwhile, on a separate energy front, the turning away from nuclear energy in Japan and Germany after the 2011 Fukushima incident is raising concerns that these countries will be forced to use more fossil fuels, chiefly coal. The full implications of this have yet to be seen.
Political, Economic and Social Shifts
The world has moved on politically as well since the Copenhagen talks. The clearest sign of this came in the joint announcement late last year of commitments on greenhouse gas emissions from the U.S. and China, the world’s two biggest emitters. The U.S. will reduce its emissions by 26 to 28 percent by 2025, while China will target a peaking of its emissions by 2030.
This development marks a clear difference from Copenhagen: The willingness of China to share a stage with the U.S. and to talk about a peak year herald significant progress toward reaching a deal.
Businesses are taking note, with many preparing to announce new climate initiatives ahead of Paris. On economics, too, we have seen more studies arguing that tackling climate change can be a boon to economies and showing how to achieve the changes necessary to stay within the carbon budget while enjoying the fruits of prosperity. The New Climate Economy project, led by Felipe Calderon, ex-president of Mexico, has been a key mover in this debate. Climate finance — the assistance provided by rich countries to poorer ones to help them cut emissions and adapt to the effects of climate change — has also ramped up, with development banks taking a leading role and leveraging private sector funds.
Businesses are taking note, with many preparing to announce new climate initiatives ahead of Paris. The insurance industry, which takes a long-term view of risks, has been pushing for action. Recently, six major European oil and gas companies offered to collaborate on a carbon price. While some might argue these businesses may have motives other than concern for the world’s poor under global warming, the actions they take could be significant.
Other positive signals in the last year have included massive rallies, such as last year’s People’s Climate March in New York, and the growing movement urging individuals, institutions and businesses to divest from fossil fuels. That movement is likely to gather further pace before the Paris meeting.
More than 400,000 people walk in the People's Climate March, which filled up the streets of New York City in Sept. 2014.
Credit: Light Brigading/flickr
Prominent public figures have also been playing an increasing role, with the most significant intervention, the encyclical Pope Francis released this spring, emphasizing the moral dimension of tackling climate change. The move attracted applause but also criticism from some climate skeptics who accused the pope of interfering in a matter of science.
Moreover, this fall, in advance of the Paris talks, the U.N. and world governments are preparing to set out Sustainable Development Goals to take over for the Millennium Development Goals that expire this year. The SDGs will have climate change not as an add-on, but as a core issue, because of its wide-ranging effects on issues from water scarcity to agricultural productivity, gender equity and human migration. The effort going into the SDGs, which are viewed as crucial by development experts, will have a beneficial effect on the battle against climate change.
Perceptions and Trends
While many of the developments in the past six years appear to bode well for Paris, there have also developed a number of perceptions that could jeopardize both an agreement and our ability to tackle climate change.
Most important was that of Copenhagen itself, which was widely painted as a total failure, despite the progress achieved there. The talks have never managed to throw off that shroud of negativity, and this puts the stakes at Paris as high as they can be. If COP 21 fails, it is hard to see how the U.N. process can limp on.
The perception of a pause in global warming is another serious problem, because it has allowed climate skeptics to claim that warming is not happening or is happening so slowly that it is not worth bothering about. This has now become common currency for many people. Scientists are clear that this analysis is not accurate: The world is still heating up, and there are good reasons to think the small slowdown in the rise in temperatures is temporary, probably caused by the absorption of heat by the oceans.
Among the mechanisms developed to help us reduce emissions, carbon trading once took pride of place. But the U.N.’s Clean Development Mechanism — by which rich countries offset their emissions by financing projects such as solar power and wind farms in the poor world — has suffered a series of blows and is looking moribund, following the near-collapse of the EU’s emissions trading scheme. If such offsets are to continue to 2020 and beyond, they badly need a shot in the arm at Paris. Otherwise, new means of channeling climate funds must be proven to work.
Secretary-General Ban Ki-moon (center left) attends a resumed session of the UN Climate Change Conference in Copenhagen in Dec. 2009.
Credit: UN Photo/Mark Garten/flickr
Yet another trend that differentiates the setting for COP 21 from that of COP 15 is the recent increase in coal consumption. “Party time for coal” is how one energy trader has characterized the past few years, as tumbling prices and rising use have led to a resurgence in the fortunes of this carbon-intensive fuel in many parts of the world. The result has been, particularly in poor countries, the building of more inefficient, old-style coal-fired power stations. Leading bodies such as the International Energy Agency and the OECD have warned that this is probably the most serious threat to tackling climate change, and it may not be solved by the Paris talks. When new coal-fired power stations are built, they are likely to continue operating for as long as half a century, locking the world in to high levels of emissions.
Finally, two years after Copenhagen, the world passed an important milestone: Human population reached 7 billion. The sheer complexity of ensuring all are fed, have decent lives and opportunities, and are lifted out of poverty increases as our numbers increase. Many scientists argue it is perfectly possible to achieve these goals without breaking through climate thresholds, but it will be tough.
In the lead-up to Paris, the most valuable commodity will be the willingness of the world’s governments to come to a deal. Whether this has changed since the Copenhagen talks remains to be seen. Many of the signs are pointing in that direction, but ultimately the choice of whether to listen to scientists, citizens and businesses lies with ministers and their leaders.
Reprinted from Ensia with permission.
Study: Warming May Bring Heightened Salmonella Risk
By Chelsey B. Coombs
Living along the shoreline may be nice, but a new study suggests that as climate change makes extreme weather and temperature events more frequent, cases of salmonella poisoning may become more prevalent, too, especially in some coastal communities.
Each year, it is estimated that 1 million people in the United States become sickened from salmonella. The stomach-crippling illness is caused by a bacteria that occurs naturally in the gut of many animals, such as cows and chickens.
Cows at the trough on a farm in Scaggsville, Md. Researchers based their study on salmonella data collected across that state.
Credit: Cyndy Sims Parr/flickr
These bacteria often travel with the waste of the animal, which can transfer the pathogen to water or soil used to grow crops. Salmonella spreads easily with contact, which makes lots of organisms subject to infection.
Kristi S. Shaw, a researcher at the University of Maryland School of Public Health and co-author of the study, published this month in the journal Environment International, said she and her fellow researchers set out to determine how environmental conditions affect salmonella outbreaks.
“Salmonella, just like any bacteria that responds well to heat, is going to spread whenever you have warmer temperatures,” Shaw said. “We wanted to look past outbreaks caused by a group of people getting sick at a church cookout or something like that, to the less defined outbreaks caused by environmental variables like temperature.”
The researchers focused their study on the state of Maryland and first looked to data from the Maryland Foodborne Diseases Active Surveillance Network (FoodNet). This Centers for Disease Control and Prevention-funded project tracks confirmed cases of salmonella and other illnesses and provides researchers with specific genetic information about salmonella. Maryland reported a little more than 9,500 salmonella cases from 2002 to 2012.
They next turned to temperature and precipitation data by county from the years 1960 to 1989. This data gave the researchers a baseline to determine whether a day from 2002 to 2012 was among those they considered to have the most precipitation (within the 90th percentile) or among those that had the hottest temperatures (within the 95th percentile). The days that met these criteria were added together to determine the number of extreme weather events that occurred during a particular month. The team then compared that number to the number of salmonella cases documented that month.
The study confirmed that as the number of extreme precipitation or temperature events increases, the risk of salmonella infection increases. Overall, a one unit increase in the number of days above the 95th percentile for temperature increased the risk of salmonella 4.1 percent; a one unit increase in the number of days above the 90th percentile for precipitation increased that risk 5.6 percent.
Salmonella bacteria, a common cause of foodborne disease, invade an immune cell.
In coastal areas, the risk increased 5.1 and 7.1 percent for a one unit increase in extreme temperature and precipitation events, respectively, while increasing 1.5 and 3.6 percent in non-coastal areas.
The researchers believe land use and soil type maybe the culprits behind these large differences. For instance, the Eastern shore of Maryland is mostly agricultural, while further inland there is a greater buildup of urban areas, according to Shaw.
“There are definite differences between the soil type of those areas: the drainage is different, and the coastal areas tend to have much sandier soil, so if you have a precipitation event, there will be a pretty decent amount of water that’s going to drop through the sand or dirt,” Shaw said. “In the inland counties where you have a higher amount of gravel and rock, there will be a very different carrying capacity for the water transport.”
Brenda Wilson, a microbiologist at the University of Illinois who was not a part of the study, said that while the results were not surprising, the data the researchers found does back up the assumption that “increased temperature and moisture makes bacteria (including pathogens) grow better, which increases the likelihood of exposure to them.”
Wilson also noted that the researchers “were careful to point out some of the limitations of their study, particularly regarding the narrow geographic area,” a sentiment echoed by Shaw.
“I think it will be hard to extrapolate this out to all coastal areas because the hydrology and the land use are going to be large components of whether you would see a situation like this. But given the other literature that backs this up, I think you will see more salmonella cases with temperature spikes and precipitation spikes,” Shaw said.
Missing: One Year’s Worth of California Rain
The amount of rain that California has missed out on since the beginning of its record-setting drought in 2012 is about the same amount it would see, on average, in a single year, a new study has concluded.
California’s accumulated precipitation debt from 2012 to 2014 shown as a percent change from the 17-year average using the TRMM mission’s multi-satellite observations.
Click image to enlarge. Credit: Goddard’s Scientific Visualization Studio
The study’s researchers pin the reason for the lack of rains, as others have, on the absence of the intense rainstorms ushered in by so-called atmospheric rivers, the ribbons of very moist air that can funnel water vapor from the tropics to California during its winter rainy season.
Overall, the study, accepted for publication in the Journal of Geophysical Research – Atmospheres, found that California experiences multi-year dry periods, like the current one, and then periods where rains can vary by 30 percent from year to year. Those wet and dry years typically cancel each other out.
The El Niño-Southern Oscillation, one phase of which has ushered in some of the state’s wettest years, only accounts for about 6 percent of overall precipitation variability, the researchers found.
Drought began creeping across the California landscape in 2012 and has continued to mushroom year after year as winter rains and snows were much diminished. The atmospheric rivers that normally funnel in moisture-laden air were thwarted by a persistent area of high pressure that blocked them from reaching California. This winter, precipitation that did manage to fall mostly did so as rains thanks to record-high temperatures linked to extremely warm waters off the coast, leaving the snowpack at record low levels.
The new study looked at satellite measurements of rainfall from NASA’s Tropical Rainfall Measuring Mission (TRMM) satellite, as well as a recreated climate record that used both observations and model data to gauge how much California’s annual precipitation varied and how much it was in the hole after four years of drought.
The researchers found that in an average year, the state sees about 20 inches of rain; it turns out that’s also about the amount of missing rain since 2012.
To dig out of the drought in just one winter, the state would have to see 200 percent of its normal yearly rain, to cover both that year’s rain and make up the missing amount.
That wet a winter isn’t very likely happen, Daniel Swain, a PhD student at Stanford University, said in an email. And if it did occur, it would mean major flooding, he added. Swain wasn’t involved with the new research.
The study also looked at another recent dry period, from 1986 to 1994, and found a 27.5-inch precipitation deficit over that period. While that was overall greater than the current drought, the per year rain deficit is much higher this time around, Swain pointed out.
Added to that, “temperatures in CA during the current drought have been warmer than during any previous drought on record, which has greatly amplified the effect of the precipitation deficits,” and helped fuel the wildfires currently flaring up around the state, Swain said.
Many are hoping the current El Niño will make a serious dent in the drought, as it looks to become a strong event, and those are associated with higher odds of increased winter rains over at least parts of the state.
The study found that the whole El Niño-Southern Oscillation cycle only accounts for about 6 percent of the variation in yearly California precipitation. That cycle encompasses not just strong El Niños, but weak ones, as well as neutral and La Niña conditions, and when separated out “very strong events (like the El Niño currently underway) exert a far greater influence upon California climate than weak ones,” Swain said. So this year’s El Niño could play a major role in what precipitation California sees.
What’s important this year, Swain said, is where the precipitation falls and how much of it falls as snow to build back up the snowpack that keeps water flowing into reservoirs come the warm, dry days of summer.
Drought May Stunt Forests’ Ability to Capture Carbon
Forests are sometimes called the lungs of the earth — they breathe in carbon dioxide in the atmosphere and store it in tree trunks until the forest dies or burns. A new study, however, shows that forests devastated by drought may lose their ability to store carbon over a much longer period than previously thought, reducing their role as a buffer between humans’ carbon emissions and a changing climate.
The study, published Thursday in the journal Science by a team of by researchers at the University of Utah and Princeton University, shows that the world’s forests take an average of between two and four years to return to their normal growth and carbon dioxide absorption rate following a severe drought — a finding that has significant climate implications.
Colorado forests are still recovering from drought.
Credit: Leander Anderegg
“This means that these forests take up less carbon both during drought and after drought,” study lead author William Anderegg, an assistant professor of biology at the University of Utah and a researcher at Princeton University, said.
Forests act as a carbon sinks by absorbing human-emitted carbon dioxide from the atmosphere and storing it in trees’ woody roots and stems. As climate change affects forests, they’ll store less carbon dioxide because drought stresses them and hinders their ability to grow, making man-made global warming even worse. Eventually, forests could become a source of carbon instead of storehouse of it.
“In some scenarios in the coming century, due to things like drought, wildfire, insects, (or) disturbances, forests start to lose more carbon than they take up, and they become a carbon source,” Anderegg said. “It’s a vicious cycle. (Forests) accelerate climate change and more climate change kills more forests.”
Using tree ring data, Anderegg’s team measured the recovery of tree stem growth following droughts dating back to 1948 in more than 1,300 forests worldwide. The average length of growth recovery in forests across the globe ranged from two to four years. Tree growth on average was 9 percent slower than normal during the first year following a drought and 5 percent slower in the second year. The driest forests recovered the slowest.
Over the course of a century, the lasting effects of drought could lead to 3 percent lower carbon storage in semi-arid forests, such as those in Arizona, Colorado and New Mexico, according to the study. That’s equivalent to 1.6 metric gigatons of carbon when considering all semi-arid ecosystems worldwide. (Between 1990 and 2007, forests worldwide stored roughly 2.4 gigatons of carbon annually, according to a 2011 University of Alaska-Fairbanks study.)
Drought-damaged forests in the Rocky Mountains could take years to recover.
Credit: Leander Anderegg
Scientists unaffiliated with the study said it highlights a flaw in climate models and can help update their assumptions about the ability of forests to sequester carbon.
“It’s an interesting paper,” Steve McNulty, a research ecologist at the U.S. Forest Service’s Southern Research Station in Raleigh, N.C., said. “The paper spells it out. If you have a model that doesn’t account for this ecosystem response (drought), it’s going to overpredict carbon sequestration.”
Matthew Ayres, a biology professor at Dartmouth College, called the paper “a fascinating study.”
There has long been reason to expect that forests could take many years to recover from drought, “but it was previously impossible to estimate so even our most sophisticated large-scale models have essentially ignored it,” Ayres said.
“Now we know that droughts in arid pine forests reduce carbon sequestration from the atmosphere by gigatons more than we had been estimating,” he said. “This study helps us understand the powerful feedbacks between people, forests and climate that will be prominent in shaping the properties of the planet that we hand off to our children.”
Editor’s Note: Stephen W. Pacala, a member of Climate Central 's board of directors and a Princeton University ecology professor, is one of this study’s 13 co-authors.
What Warming Means for 4 of Summer’s Worst Pests
Summer may mean it’s time for outdoor fun in the sun, but it’s also prime time for a number of pests. All that extra time outdoors can bring everything from poison ivy rashes to exposure to Lyme disease from tick bites. And of course there’s that ubiquitous summer menace, the mosquito.
With the rising temperatures brought about by global warming, the risks posed by these pernicious pests could also be increasing. A warmer climate can mean expanded habitats for many pest species, as well as increases in their numbers. Here’s what research suggests will happen with four key summertime pests as the world warms:
Predicted change in the range of the Asian Tiger mosquito with warming from high levels of greenhouse gas emissions.
Click image to enlarge. Credit: Rochlin et al./PLOS ONE
Is there any pest more synonymous with summer than the mosquito? There are many species of the annoyingly buzzing biters found in different areas around the country. While some are merely an itchy nuisance, others come with the risk of spreading diseases like malaria, West Nile virus and dengue fever, including the invasive Asian Tiger mosquito, which first appeared in the U.S. in 1985.
As temperatures around the country rise, the areas that are conducive to such mosquitoes could expand, and the insects could start to emerge earlier in the year, meaning more opportunities for bites that could spread disease. After an unseasonably warm late spring, summer, and early winter in 2012, the U.S. experienced a West Nile Virus outbreak linked to the Asian Tiger mosquito, with some 5,600 people becoming infected.
Asian Tiger mosquitoes tend to die off when temperatures venture outside a range from 50°F to 95°F and when relative humidity dips below 42 percent. A Climate Central analysis examined how warming would affect this range for cities around the country, showing how many more “mosquito suitable” days there were now compared to 1980. See how your city has fared in the dropdown menu below.
One key question in terms of the health impact of expanded mosquito territory is whether the new climates they venture into will be as welcoming to the pathogens they can carry. Arizona has a lot of Aedes aegypti mosquitoes, another invasive mosquito species, but no dengue, which it can often carry, Mary Hayden, a scientist with the National Center for Atmospheric Research in Boulder, Colo., said. Why this is isn’t known, but Hayden and her colleagues suspect it is because the harsh desert climate doesn’t allow the mosquitoes to live long enough for dengue to undergo its full development cycle.
But there have been small outbreaks of dengue in Texas near the Mexican border, Hayden said, as well as a disease found in the Caribbean, called chikungunya, in Florida. Health officials are closely watching these areas for larger outbreaks, she said.
Click image to enlarge.
Time to stock up on the calamine lotion.
Poison ivy is a well-known scourge for those who spend time outdoors in the summer. Already more than 350,000 cases of poison ivy occur annually in the U.S., according to the National Wildlife Federation, and that number could go up as the climate changes.
The impacts of climate change on poison ivy have more to do with the cause behind rising temperatures than the warming itself. Plants need carbon dioxide — the key heat-trapping greenhouse gas — to fuel photosynthesis. Experiments that exposed poison ivy plants to different levels of CO2 have found that “poison ivy grows faster when there’s more CO2” and it produces more leaves that carry the plant’s toxic oil, Doug Inkley, a NWF scientist, said.
Those oils, which put the “poison” in poison ivy, can vary in their chemical structure, and high CO2 levels also cause the plants to produce a more toxic form, “so climate change is not doing us any favors there,” Inkley said.
Expected range of deer ticks with warming by 2080.
Click image to enlarge. Credit: NCA
Anyone who’s been out for a walk in the woods on the East Coast is familiar with the phrase “tick check.” The main reason for such concern over these tiny creatures is the ability of certain species, in particular the so-called deer tick, to transmit diseases such as Lyme disease and anaplasmosis.
The CDC estimates that about 300,000 people in the U.S. are diagnosed with Lyme disease each year, primarily in the Midwest and Northeast. (While ticks are found throughout the South, they have a more diverse array of species to feed on there, and so are less likely to encounter the deer and mice that can harbor Lyme disease.)
As temperatures rise, there is concern that ticks could spread into newly suitable habitat and bring Lyme disease and other pathogens with them. They have already expanded northward into Canada, where the number of reported cases of Lyme disease doubled between 2009 and 2012, according to Canadian government figures — a trend attributed to more locally acquired cases.
That northward expansion is expected to continue, as shown in the National Climate Assessment, while a much smaller retraction on the southern end of their range is also anticipated. The worry is that people who aren’t used to having to think about Lyme exposure won’t know to take proper precautions to reduce their risks.
Warming could also cause explosions in tick populations, as higher winter temperatures fail to thin out overwintering populations, Inkley said. More ticks means more chances for Lyme to be transmitted. Earlier thaws and later frosts could also mean that ticks are active for a longer period, again increasing the risk of Lyme transmission.
But, just as with mosquitoes, it is unclear whether changes in the climate and conditions of new habitats will be as conducive to the Lyme bacterium and other diseases as they are to ticks.
Possible expanded range of the imported red fire ant with climate change.
Click image to enlarge. Credit: L.W. Morrison et al.
Red Fire Ants
This last pest is another invasive species. The imported red fire ant, as it is colloquially known, came to the U.S. from its native South America sometime in the 1930s or ‘40s, likely as a stowaway in ship ballast. The species now covers more than 300 million acres, mostly in the Southeast, where it came ashore, according to the NWF.
The ants, which bite and sting as a single mass, thrive in places where winter low temperatures don’t dip too low. “The colder it is, the slower the colonies grow and the more mortality occurs,” Lloyd Morrison, a National Park Service ecologist who has studied them, said in an email. “One very cold period in the winter could kill colonies outright or prevent colonies from reproducing.”
With warming, those low temperatures don’t get as cold, meaning colonies could be less inhibited. Morrison did a study in 2005 that modeled the potential expansion of the imported red fire ant with climate change and found that warming temperatures would expand suitable habitats by about 5 percent by mid-century and then by 21 percent towards the end of the century. This would mean imported red fire ants could be found as far north as Nebraska, Kentucky and Maryland.
And while these ants can certainly provide an unpleasant encounter for any unwitting humans who come across them — their en masse bites inject their victims with venom that produces a burning sensation and raises blisters that can become infected — they are actually more of a threat to local wildlife. Swarms of ants can easily overwhelm young birds in ground nests and small animals like mice, Inkley said.
Thinking about all of these summer fun-ruining pests may have you scratching some imaginary itch and eyeing the outdoors warily, but it doesn’t mean you can’t enjoy what nature has to offer, Inkley said.
“We strongly believe that people should get out of doors,” he said. It just means being vigilant and prepared for nature’s not-so-nice side.
Warming May Boost Wind Energy in Plains States
By Chelsey B. Coombs
Powerful winds are commonplace in the U.S. prairie states, which experienced walls of dirt swept into the air by these gusts during the Dust Bowl. While today's winds don't often carry the huge quantities of dust that they did in the 1930s, they’re stirring up something significantly more useful in states like Kansas, Oklahoma and Texas – energy.
A study published last month in the journal Renewable Energy suggests that climate change may make these states windier in the coming years, which could be a boon to the nation’s renewable energy industry and the already thriving wind energy operations in those states.
A wind technician inspects a nacelle at the Los Vientos wind farm near Harlingen, Texas.
Credit: Duke Energy/flickr
Texas had the greatest amount of installed wind capacity in the U.S. at the end of the first quarter of 2015, generating enough energy to power 3.6 million homes, according to the American Wind Energy Association. Oklahoma and Kansas weren't far behind, being fourth and ninth, respectively.
The steady rise of global temperatures – driven by the buildup of heat-trapping greenhouse gases – was one of the driving factors behind the study. Projections by the Intergovernmental Panel on Climate Change (IPCC) suggest that if countries meet their current greenhouse gas emission reduction goals, temperatures may rise 2.3 to 2.9 degrees Celsius by 2100. If emissions continue unabated, temperatures may rise 4.1 to 4.8 degrees Celsius.
“The sun is emitting energy uniformly, but the earth takes it up unevenly. To me, that’s the starting point of why pressure and wind come about on the earth at all,” Robert Erhardt, a Wake Forest University assistant professor and one of the study’s authors, said. “I was interested in looking to see if there were any projected changes in wind speed and ultimately wind energy density as a result of climate change.”
Erhardt and Dana Johnson, a Wake Forest University student and study co-author, used four climate models from the North American Regional Climate Change Assessment Program (NARCCAP) to map wind energy density throughout the United States. After calculating and mapping the wind energy density of every region from 1968 to 2000, the team did the same using computer modelling for the years 2036 to 2070.
While some of the climate models suggest modest decreases in wind in some areas, across all four models, the wind energy densities of Oklahoma, Kansas and Northern Texas are projected to increase at least 2 percent by the middle of the century.
“These states are already windy, they already have wind farms, there are records and legislation promoting more of this, so it was a happy coincidence, really, that this was also the region that we projected to get windier,” Erhardt said.
The Smoky Hills Wind Farm north of Ellsworth, Kan.
Credit: brent flanders/flickr
The researchers focused on three counties within those states to determine how much additional power each person would get with the projected midcentury wind energy density increase.
For example, the 75 turbines in Kiowa County, Kan., which is about 120 miles west of Wichita, have the capacity to generate 120 MW of power; that’s enough to fuel around 7,900 homes every month. Even if Kiowa County stopped installing new wind turbines, a 2 percent increase in wind energy density would allow the existing turbines to generate an extra 10 MW of power. Each of the county’s 2,500 residents would therefore have an additional 3.9 kW of power to use, enough for each of them to run a clothes washer and drier all day, every day.
Mark Jacobson, a professor of civil and environmental engineering at Stanford University, said that though the changes in wind energy density that the study demonstrates are modest, they project wind energy’s staying power.
“The good news is that, whether future wind speeds increase or decrease due to climate change, the changes are relatively small,” Jacobson said. “Given the vast wind resources of the Great Plains, climate change will not cause a loss of wind power generation to the U.S.”