Category Archives: Basic Science of Global Warming

How scientists linked the California drought to climate change

A drought-stricken vineyard in Napa Valley. Source: John Weiss/Flickr

California has officially entered its fourth consecutive year of drought, and is trapped in its worst water shortage situation ever.

Because we know that human-caused climate change cantrigger and exacerbate drought conditions, media, public officials, California residents and scientists have all been wondering for years if rising global temperatures likely caused or contributed to the current drought in California.

The short answer: Yes, they did.

Weather won’t cooperate

Scientists have suspected for some time now that a certain meteorological condition lies behind the long-lasting California drought. The persistence of a stubborn high-pressure system off the coast has been preventing storm systems from reaching California and instead deflecting them to Alaska and elsewhere.

While weather events are almost always multi-causal, the California drought is largely a result of this atmospheric weather pattern. The question is whether climate change has influenced the development, or sustenance, of this system.

Stanford scientists connected the dots

When destructive events happen, people want to know right then and there what’s going on— whether it’s an epidemic, riot or weather disaster.

But evaluating an extreme weather event for climate change influences is a scientific process that takes several months of computer simulations and statistical techniques. It can frustrate some who demand an answer right away.

Well, the results from several, month-long studies are finally in. Scientists from Stanford have found that the meteorological conditions that have caused the California drought are far more likely to occur in today’s warming world than in one without human-caused emissions of greenhouse gases.

It shows us – ironically and tragically – that the state thatleads the nation in curbing greenhouse gas emissions is right now suffering more than any other from climate change.

California is not alone

The California drought attribution studies are a subset of alarger collection of recently published studies that explain 16 extreme weather and climate events of 2013.

Twenty research teams explored the causes of events such as heat waves in Australia, New Zealand, Korea, Japan, China, and Europe; torrential downpours in Colorado and India, a blizzard in South Dakota, and a cold spell in the United Kingdom.

The studies overwhelmingly indicated that all heat waves were largely attributable to human-caused climate change. One study even suggested that the heat wave in Korea has been made 10 times more likely due to human influence.

The extreme rainfall events in India were concluded to have been more likely in a human-influenced world, but data for assessing precipitation events is rather limited as compared to heat waves. Further, studies concluded that the extreme rainfall event in Colorado, the blizzard in South Dakota, and the cold spell in the U.K. were unlikely to have been influenced by climate change.

Climate change is happening. Now.

So for anyone who may still think that the consequences of climate change are in the distant future, this collection of studies suggest that human-caused climate change is right now causing a crisis in America’s most populous state and the world’s eighth largest economy.

California reminds us that climate change is a major concern for societies everywhere, and that all nations are vulnerable to extreme weather events. It’s time we roll up our sleeves and stop this, once and for all.

This blog originally appeared on EDF Voices 

Posted in Basic Science of Global Warming| 3 Responses

Why California thirsts for rain and the East Coast gets soaked

Source: Flickr/Jared Tarbell

If you think the weather’s acting strange, you’re correct. Extreme weather in the United States is trending upward, and human-caused climate change has already been blamed for much of it – most recently in connection with theCalifornia drought.

But along with extreme weather we’re also getting extreme contrasts. What on Earth is going on when New York gets endless rain and San Francisco none, and when one part of the country is freezing while another suffers under record heat?

You guessed it, rising temperatures have something to do with it – and here’s how.

Rain patterns are changing

In the Northeast, the combination of more moisture in the atmosphere from a warmer world and changes in circulation patterns are bringing more rain. In the Southwest, meanwhile, rainfall is suppressed by a northward expansion of high pressure in the subtropics.

The crippling drought now plaguing California is due to a persistent high pressure system off of the coast that is deflecting storms away from the region. A recent study shows that these systems are much more likely to occur with human-caused climate change.

Rain is more intense

Heavy downpours are controlled by cloud mechanisms and moisture content, which are both changing as global temperatures rise. Clouds that can dump a lot of rain are more common in a warmer atmosphere.

More evaporation has led to more moisture in the atmosphere which, in turn, leads to more intense rainfall when it rains. That helps explain why the entire U.S. is experiencing more heavy downpours – even in the drought-stricken West.

Droughts are taking hold

Rain and evaporation will determine how moist the soil will be. So although evaporation is increasing nationwide due to warmer temperatures, higher precipitation in the Northeast yields a net increase in soil moisture in that part of the country.

In the Southwest, on the other hand, the drop in overall precipitation brings drier conditions that spawn or magnify drought. As the soil there dries out, the incoming sunlight will heat the ground instead of evaporating water from the soil. This creates a vicious cycle of more heat and less rain.

Flooding is more common

The potential for flooding, meanwhile, depends a lot on what's going on with the soil. The higher the soil moisture content, the higher the chance that there will be more runoff from rainfall.

Because soil moisture is increasing in the Northeast, flooding events are on the rise. Fortunately for the region, many heavy rain storms occur in the summer and fall when soil moisture is low and the ground can absorb more water.

On the other hand, the sea level has risen by a foot since the 1900s in the Northeast. That, in turn, contributes to more flooding.

Disaster costs are also rising – but there is hope

In 2013, intense storms, severe regional drought, and extreme flooding led to more than $9 billion in disaster costs in the U.S. alone. It’s uncertain what the total bill was if you factor in ongoing agriculture, human health and infrastructure losses from changing weather conditions

Unless we curb emissions of heat-trapping gases, scientists expect these trends to continue and worsen – and the contrast between wet and dry areas of the U.S. will likely become even sharper. Our hope now is that the push for climate action amps up so we can finally set ourselves on a better path for the future.

This post originally appeared on EDF Voices 

Also posted in Greenhouse Gas Emissions, Science| 1 Response

"Risky Business" stands out in growing sea of climate reports

Receding beach on North Carolina's Outer Banks. Source: FEMA/Tim Burkitt

(This blog originally appeared on EDF Voices)

This blog post was co-authored by Jonathan Camuzeaux.

Put Republican Hank Paulson, Independent Mike Bloomberg, and Democrat Tom Steyer together, and out comes one of the more unusual – and unusually impactful – climate reports.

This year alone has seen a couple of IPCC tomes, an entry by the American Association for the Advancement of Science and the most recent U.S. National Climate Assessment.

The latest, Risky Business, stands apart for a number of reasons, and it’s timely with the nation debating proposed, first-ever limits on greenhouse gas emissions from nearly 500 power plants.

Tri-partisan coalition tackles climate change

The report is significant, first, because we have a tri-partisan group spanning George W. Bush’s treasury secretary Paulson, former mayor of New York Bloomberg, and environmentalist investor Steyer – all joining forces to get a message through.

That list of names alone should make one sit up and listen.

Last time a similar coalition came together was in the dog days of 2009, when Senators Lindsay Graham, Joe Lieberman, and John Kerry were drafting the to-date last viable (and ultimately unsuccessful) Senate climate bill.

Global warming is hitting home

Next, Risky Business is important because it shows how climate change is hitting home. No real surprise there for anyone paying attention to globally rising temperatures, but the full report goes into much more granular details than most, focusing on impacts at county, state and regional levels.

Risky Business employs the latest econometric techniques to come up with numbers that should surprise even the most hardened climate hawks and wake up those still untouched by reality. Crop yield losses, for example, could go as high as 50 to 70 percent (!) in some Midwestern and Southern states, absent agricultural adaptation.

The report is also replete with references to heat strokes, sky-rocketing electricity demand for air conditioning, and major losses from damages to properties up and down our ever-receding coast lines.

Not precisely uplifting material, yet this report does a better job than most in laying it all out.

Financial markets can teach us a climate lesson

Finally, and perhaps most significantly, Risky Business gets the framing exactly right: Climate change is replete with deep-seated risks and uncertainties.

In spite of all that we know about the science, there’s lots more that we don’t. And none of that means that climate change isn’t bad. As the report makes clear, what we don’t know could potentially be much worse.

Climate change, in the end, is all about risk management.

Few are better equipped to face up to that reality than the trio spearheading the effort; Paulson, Bloomberg and Steyer have made their careers (and fortunes) in the financial sector. In fact, as United States Treasury secretary between 2006 and 2009, Paulson was perhaps closest of anyone to the latest, global example of what happens when risks get ignored.

We cannot – must not – ignore risk when it comes to something as global as global warming. After all, for climate, much like for financial markets, it’s not over ‘til the fat tail zings.

Also posted in Cars and Pollution, Economics, Extreme Weather, Greenhouse Gas Emissions, Health, Jobs, News, Policy| 1 Response, comments now closed

Study: Climate change may push hurricanes farther north, south

A satellite image of Irene, a Category 1 hurricane, as it made landfall in North Carolina in August of 2011. Source: NASA/NOAA GOES project

The hurricane season of 2014 just kicked off, and with two devastating storms wreaking havoc along the northeastern United States coast over the last few years, it’s no wonder everyone’s on edge.

We’re concerned about hurricanes becoming more frequent and intense, and about the worsening storm surge caused by a rise in sea levels. But flying under the radar is a fourth link between hurricanes and climate change: how climate change affects the location of hurricanes.

new study led by researchers at the National Oceanic and Atmospheric Administration, the Massachusetts Institute of Technology and Princeton University found that hurricanes have been shifting pole-ward at a rate of 30 to 40 miles per decade over the last 30 years.

It means they are moving closer to major population centers such as Washington, New York and Boston.

The likely cause? Human-caused climate change.

The migration of hurricanes has “potentially profound consequences for life and property,” the authors of the study warn in an article published recently in the journal Nature.

Increasing hazard exposure and mortality risk from tropical cyclones may be compounded in coastal cities outside the tropics, while being offset at lower latitudes.”  

Linking climate change to hurricane location

This finding is an important advancement in scientists’ understanding of how climate change has already contributed to extreme weather events. Research shows that the rise in global temperatures already causes more warm days, heat waves, and heavy rainfall.

Detecting trends in hurricane activity has been difficult, however, due to inconsistent and often unreliable historical data.

To get around this data challenge, the scientists at NOAA, MIT and Princeton developed a new technique that relies on a dependable subset of the data, and which teases out natural events such as El Niño to detect a distinct relationship between hurricane activity and climate change.

Their conclusion: Hurricanes are drifting toward the poles most likely due to an expansion of the Hadley Cell, a permanent atmospheric circulation feature that carries heat from the tropics to the Earth’s temperate zones.

Scientific understanding is that the Hadley Cell expansion is a result of the increase in heat-trapping gases in the atmosphere from human activities. So as we continue to drive cars, generate electricity at fossil-fueled power plants, cut down trees, and farm – we are indirectly pushing hurricanes farther north and south.

The new study is groundbreaking not only because it uses a novel technique, but also because it links a hurricane trend to climate change.

What we know so far

So where are we today with hurricanes and climate change?

Scientists studying hurricanes:

  • Have found no observed trend in frequency
  • Have not been able to detect trends in intensity  and duration
  • Are confident that human-caused sea level rise is contributing to storm surge
  • Expect the frequency of intense storms to increase in the future
  • Have now detected a robust trend in location shifts that is likely due to human activity

This new research presented in Nature suggests that hurricanes are migrating toward the poles and may devastate densely populated coastal regions that had previously, for the most part, been spared such storms.

It’s yet another reason why we must act now to curb carbon pollution and limit climate change.

This post first appeared on EDF Voices

Also posted in Clean Power Plan, Extreme Weather, Greenhouse Gas Emissions| 2 Responses, comments now closed

Hundreds of Thousands Support Standards to Ensure a Healthy Low-Carbon Future

This is a fact that always stuns people:

There are currently no national limits whatsoever on carbon pollution from U.S. power plants, the single largest source of this pollution in the country.

But last year, the Environmental Protection Agency (EPA) announced a proposal that could change that fact for future power plants.

EPA’s proposal would set America’s first-ever national carbon pollution standards for future power plants – a major victory in the fight against climate change.

The Carbon Pollution Standards for New Power Plants are an absolutely necessary, common sense step toward limiting the pollution emitted through our country’s power generation. These standards will help protect our children from harmful smog, curb respiratory problems, and shield our communities from extreme weather. They will also drive innovation, so that America can continue to lead the world in the race to develop cleaner, safer power technologies and infrastructure.

About 300,000 EDF activists have sent comments to EPA in support of these vital standards.

(The comment period for these proposed standards ends today — but you still have a few hours to comment, if you haven’t yet! You can write a comment here)

The Carbon Pollution Standards for New Power Plants also have the support of millions of other Americans including moms, and members of health groups, environmental groups, power companies, Latino groups, the NAACP, faith groups and many more.

Here are just a few examples of what people have been saying about the proposed standards:

American Academy of Pediatrics

Children represent a particularly vulnerable group that is likely to suffer disproportionately from both direct and indirect adverse health effects related to climate change. … Because of their physical, physiologic, and cognitive immaturity, children are often most vulnerable to adverse health effects from environmental hazards. Environmental hazards may shift as the climate changes, and children are likely to suffer disproportionately from those changes.

The Clean Energy Group

EPA’s proposed rule for new sources provides the industry with a higher degree of business and regulatory certainty. Based on our review of the proposal, recent projections by the U.S. Energy Information Administration, and current market dynamics, we do not anticipate that the proposed greenhouse gas performance standards for new sources, with the recommendations included here, would adversely affect the reliability of the electric system…We agree that EPA has sufficient scientific and legal basis to regulate greenhouse gases from new EGUs under section 111 of the CAA.

U.S. Conference of Mayors

Over 1,000 mayors have signed USCM’s Climate Protection agreement…But local governments alone cannot shoulder the entire burden or responsibility of limiting GHG emissions and protecting the health of our citizens. A national regulatory framework is required to achieve the substantial and absolutely necessary reduction in GHG emissions. Therefore, we commend the U.S. EPA for its efforts in this regard and encourage final promulgation of these CAA rules.

National Latino Coalition on Climate Change and Green Latinos

It is because Latino and other traditionally under-represented communities are so disproportionately impacted by these harmful pollutants that NLCCC must urge the EPA to adopt the strictest possible carbon pollution standards for new power plants that will adequately protect our communities…These rules are essential to protect the health of our members and necessary to guarantee the safety of the air of Hispanic communities nationwide.

Creation Justice Ministers

I am here today to offer our faith community’s response to the rule on new power plants. We view climate change as the moral issue of our time, and feel we have an obligation to reverse the implications of our careless actions. As Christians, we are called to be stewards of the land that was gifted to us and ensure that we leave this planet better for the next generation.

(You can read more quotes on our fact sheet)

These standards are an important part of President Obama’s Climate Action Plan to control dangerous carbon pollution, pollution we are seeing all too clearly now that is harming our country and world.

The Third National Climate Assessment released a few days ago finds beyond a reasonable scientific doubt that Americans are being affected by climate change, which is directly affected by the increase of emissions of heat-trapping gasses such as carbon.

The NCA says:

Evidence for climate change abounds …The sum total of this evidence tells an unambiguous story: the planet is warming.

The NCA also finds that Americans now experience respiratory illnesses, heart problems, and water-borne diseases as a result of climate change.

The costs of climate inaction are already with us, and threaten to increase for our children and grandchildren. But the Carbon Pollution Standards for New Power Plants are an excellent step towards a brighter future, a more sustainable infrastructure, and a stronger nation.

(EDF's Charlie Martin helped write this post)

Also posted in Clean Power Plan, Greenhouse Gas Emissions, News, Policy, Science| 2 Responses, comments now closed

The way forward to kicking our carbon addiction

Photo credit: Billy Wilson cc

How would you respond to an upsetting medical diagnosis? Probably first with shock and fear, then you’d ask the doctor about realistic treatment options. That’s how it works for an individual, but what about when seven billion people get the bad news at the same time?

That’s what happened yesterday, when the White House released another troubling National Climate Assessment (NCA). It described a condition that’s going to get significantly worse without intervention – with troubling symptoms already apparent.

Now, to be fair, this NCA wasn’t really news in the “I didn’t see that coming” sense. Just like a patient who has been told to stop smoking for years, there has been plenty of warning that our “unfiltered” smokestacks are causing serious damage to our environment and health. Last month, in fact, the International Panel on Climate Change issued its fifth report, and this is the third National Climate Assessment – each making more specific estimates of the climate dangers ahead. And yet, we can’t quit our pack-a-day habit.

The disturbing news is all here: Threats to agriculture from drought, danger for coastal residents and businesses from rising seas, more frequent intense hurricanes, more asthma attacks for kids, the spread of insect borne disease, and much more.

But the good news is that this disease has a cure. In fact, in just about four weeks, the United States is poised to take a very important step towards improving the currently predicted outcome. On June 2, EPA is planning to announce limits on carbon emissions from existing power plants, which are America’s largest source of climate pollution – about a third of the total we produce.

When EPA announces the new standards, what will probably surprise most people is that the agency doesn’t already have limits on this type of pollution. A recent poll indicates that 56% of Americans assume we currently have these protections. That’s an understandable belief since EPA limits most other forms of air pollution, but up to now utilities have been free to put as much of this stuff as they can crank out in our common atmosphere. And all that pollution has a very real cost borne by society.

Of course, as with all other proposed air pollution rules, there will be a small but powerful group who howl in protest. They did it when EPA limited toxic mercury, sulfur, smog and other dangerous pollutants. I’m sure you’ll hear that ending unlimited carbon pollution will wreck our economy and bankrupt us all. But what those people won’t tell you is that studies have shown that every past air pollution rule has actually helped the U.S. economy, with benefits outweighing costs by a substantial margin.

The new rules alone won’t cure climate change. But, along with actions on cars and trucks that have already been announced, they are a substantial first step. These standards will also push utilities to modernize, help grow clean energy jobs, and give a boost to entrepreneurs who are looking for ways to power our economy more cleanly. (EPA Administrator Gina McCarthy has said the agency is exploring ways to make the rules flexible, allowing states and companies to find innovative ways to meet the standards.)

Cures are never painless, but they’re usually a lot better than the disease. And everyone knows that the sooner you act, the better the outcome. So let’s take yesterday’s diagnosis seriously, and when EPA announces the new carbon standards on June 2, let’s make sure Congress knows we all want a healthy future.

This post first appeared on our EDF Voices blog.

Also posted in Clean Air Act, Clean Power Plan, Greenhouse Gas Emissions, Health, Policy| 2 Responses, comments now closed

New report: How climate change is impacting where you live

The National Climate Assessment (NCA) report, prepared by the U.S. Global Change Research Program, is essentially the U.S. equivalent of the Intergovernmental Panel on Climate Change (IPCC): Using the best available science, over 300 experts synthesized current understanding of observed and future climate changes and impacts, particularly in the U.S. The third ever NCA was released today, and concludes beyond a reasonable scientific doubt that Americans are being affected by climate change.

Among the findings:

  • U.S. average temperatures have increased by 1.3 to 1.9ºF since record-keeping began in 1895, and most of this warming has occurred since 1970
  • Heavy precipitation has increased in many parts of the country
  • Extremes such as heat waves, droughts, floods, and North Atlantic hurricanes are more frequent and/or intense
  • Summer sea ice in the Arctic has halved since record-keeping began in 1979
  • Sea level rise has increased coastal erosion and storm surge damage

These changing conditions produce a variety of tangible stresses on society by affecting human health, water resources, agriculture, energy, infrastructure, and natural ecosystems. The particular impacts vary by region, but no corner of the country is immune to the change.

So what’s happening where you live?

Source: National Climate Assessment

Unless we take immediate action to curb our emissions of heat-trapping gases, the foreseeable future will be plagued by further warming and worsening impacts. The good news is that because we know what the cause is, we also know what is needed in order to stabilize our planet. We must come together now—locally, nationally, and internationally—and work towards a better future.

This post first appeared on our EDF Voices blog

Also posted in Arctic & Antarctic, Extreme Weather, Oceans, Science| Comments closed

Correcting the maths of the "50 to 1 Project"

A nine-minute video, released earlier this fall, argues that climate mitigation is 50 times more expensive than adaptation. The claims are based on calculations done by Christopher Monckton. We analyzed the accompanying “sources and maths” document. In short, the author shows a disconcerting lack of understanding of climate science and economics:

  1. Fundamental misunderstanding of basic climate science: Pre-industrial levels of carbon dioxide (CO2) were at around 280 parts per million (ppm).[i] One of the most commonly stated climate policy goals is to keep concentrations below 450 ppm CO2. Monckton, oddly, adds 280 and 450 to get to 730 ppm as the goal of global stabilization efforts, making all the rest of his calculations wildly inaccurate.
  2. Prematurely cutting off analysis after ten years: Monckton calculates the benefits of the carbon tax over a ten-year time horizon. That is much too short to see the full effects of global warming or of the policy itself. Elevated carbon levels persist for hundreds to thousands of years.[ii]
  3. Erroneously applying Australian “cost-effectiveness” calculation to the world: This may be the most troubling aspect from an economist's point of view. Monckton first calculates the effect of the Australia-only tax on global temperatures, which is unsurprisingly low, as Australia accounts for only 1.2% of world emissions. Next, he calculates the tax’s resulting “cost-effectiveness” — defined as the Australian tax influencing global temperatures. No surprise once again, that influence is there, but Australia alone can't solve global warming for the rest of us. Then, Monckton takes the Australia-only number and scales it to mitigate 1ºC globally, resulting in a purported cost of “$3.2 quadrillion,” which he claims is the overall global “mitigation cost-effectiveness.” But this number simply represents the cost of avoiding 1ºC of warming by acting in Australia alone. Monckton has re-discovered the fact that global warming is a global problem! The correct calculation for a globally applied tax would be to calculate cost-effectiveness on a global level first. If Australia’s carbon price were to be applied globally, it would cut much more pollution at a much lower cost. And that, of course, is very much the hope. Australia, California, and the European Union are called “climate leaders” for a reason. Others must follow.

What’s the real cost of cutting carbon? The U.S. government’s estimate of the cost of one ton of CO2 pollution released today is about $40.[iii] That's also the optimal price to make sure that each of us is paying for our own climate damages. Any policy with a lower (implied) carbon price—including the Australian tax—easily passes a benefit-cost test.

With all due respect Lord Monckton, 3rd Viscount of Brenchley, your maths are way off.


[i] "Summary for Policymakers," IPCC Fifth Assessment Report, Working Group I (2013).

[ii] Results differ across scenarios, but a rough rule of thumb suggests that approximately 70% of the ‘peak enhancement level’ over the preindustrial level of 280 ppm perseveres after 100 years of zero emissions, while approximately 40% of the ‘peak enhancement level’ over the preindustrial level of 280 ppm persevered after 1,000 years of zero emissions (Solomon, Susan, Gian-Kasper Plattner, Reto Knutti and Pierre Friedlingstein, “Irreversible climate change due to carbon dioxide emissionsProceedings of the National Academy of Sciences 106, no. 6 (2009): 1704-1709). Note that this refers to the net increase in carbon dioxide in the atmosphere, not the exact molecule. Archer, David, Michael Eby, Victor Brovkin, Andy Ridgwell, Long Cao, Uwe Mikolajewicz, Ken Caldeira et al. "Atmospheric lifetime of fossil fuel carbon dioxide." Annual Review of Earth and Planetary Sciences 37 (2009): 117-134 discusses these two often confused definitions for carbon’s ‘lifetime,’ and concludes that 20-40% of excess carbon levels remain hundreds to thousands of years (“2-20 centuries”) after it is emitted. Each carbon dioxide molecule has a lifetime of anywhere between 50 to 200 years, according to the U.S. Environmental Protection Agency’s “Overview of Greenhouse Gases: Carbon Dioxide Emissions.” The precise number is under considerable scientific dispute and surprisingly poorly understood. (Inman, Mason, “Carbon is forever,” Nature Reports Climate Change 20 November 2008)

[iii] The precise value presented in Table 1 of the Technical Update of the Social Cost of Carbon for Regulatory Impact Analysis Under Executive Order 12866 for a ton of carbon dioxide emitted in 2015, using a 3% social discount rate increased is $38. For 2020, the number is $43; for 2030, the number increases to $52. All values are in inflation-adjusted 2007 dollars. For a further exploration of this topic, see Nordhaus, William D. The Climate Casino: Risk, Uncertainty, and Economics for a Warming World. Yale University Press (2013) as only one of the latest examples summarizing this kind of analysis. Nordhaus concludes that the optimal policy, one that maximizes net benefits to the planet, would spend about 3% of global GDP.

Many thanks to Michelle Ho for excellent research assistance.

Also posted in Economics, International| Comments closed

Today’s IPCC Report is A Grim Reminder that We Must Find Solutions to Climate Change

People who are fond of conspiracy theories or enjoy rejecting mainstream science might want to stop reading now. What follows is solid, well-researched science based on mountains of peer-reviewed evidence. You have been warned.

Today, the Intergovernmental Panel on Climate Change (IPCC) issued their latest report, and the picture they paint is grim.

Hundreds of scientists from countries all over the world assessed the most recent research. The result – they are more certain than ever that climate change is caused by human activity. The report says it is extremely likely that humans are the main cause for our increase in global temperatures since the mid-twentieth century.

More greenhouse gas emissions will lead to more warming, and the consequences will be felt all over the globe.

And the worst part is IPCC’s predictions may have been conservative.

The international organization, which is one of the world’s foremost authorities on climate change, reports:

  • They are 95 percent certain human activity is responsible for the rise in global temperatures from the latter half of the twentieth century to the present.
  • The chances of an extreme heat wave have more than doubled, and heavy rainfall events are expected to intensify and occur more often.
  • Ocean levels may rise by three feet by the end of this century if emissions are not curbed.

That last prediction may sound like a worst-case scenario, but other experts warn sea-level rise could actually be much worse.

As reported in the Washington Post, the Climate Change Commission predicts the oceans may rise as much as six feet by the year 2100, depending on factors such as glacial ice melting. Sea level rise at that level would be catastrophic, especially when considering its impact on storm surges.

As scary as these predictions are, there are reasons for hope. As communities across the United States and the world increasingly face extreme weather events and other consequences of climate change, we are beginning to see our leaders take more action.

Just last week the Environmental Protection Agency proposed the first nationwide limits on carbon pollution from new power plants. That’s the latest development in President Obama’s Climate Action Plan, a bold mission to take meaningful steps toward a climate change solution.

The release of the IPCC report will no doubt lead climate deniers to spread the usual disinformation. You can find almost anything on the Internet if you Google long enough, but that doesn’t make it true.

Legitimate scientific debate is a good thing — when we stick to facts that are backed by evidence and reviewed by independent experts in the field.  It’s understandable when citizens with busy lives don’t know all the facts on a complex issue like climate change, but there’s no excuse for politicians and talking heads to spread false information. Solving this problem will require a discussion grounded in science, which is why the IPCC report is so valuable.

It’s time to recognize that the billions of tons of carbon pollution we put in our atmosphere every year are causing dangerous changes to our climate — and then work together to find the best solutions.

Also posted in Greenhouse Gas Emissions, News, Science| Comments closed

Wanted: Sound Climate Science from the House Science Committee

House Committee on Science, Space and Technology Chairman Lamar Smith recently wrote an op-ed in the Washington Post that dangerously distorted the science behind man-made global warming.

It is patently false to suggest, as Chairman Smith did, that there is a “great amount of uncertainty” regarding the fundamental science underlying our understanding of the drivers of climate change. Man-made warming has been confirmed repeatedly by the vast majority of scientific organizations including NASA, the National Academies of Science and the American Meteorological Society. A recent review also reaffirmed that 97% of peer-reviewed scientific publications that address the causes of climate change endorse the consensus that climate change is real and man-made.

Chairman Smith argues that since the US decreased its greenhouse gas emissions between 2005 and 2012 we cannot be responsible for global greenhouse gas emissions. However, carbon dioxide remains in the atmosphere so long the US is responsible for more of the warming we are currently experiencing than any other nation.  In 2011, the United States’ emissions remained the second highest behind only China, a country with more than four times the population of the US.  The US continues to emit significantly more greenhouse gas per person than does any of the larger nations of the world, the few smaller exceptions are major fossil fuel producing countries. The fact that the US is not currently the single largest emitter is no excuse not to lead on addressing climate change.  The logic used by Chairman Smith implies that we should only ask the very largest emitters to clean up criteria air pollution or water pollution across the US. If we utilized that strategy our water and air would not have seen the improvements of the past 40 years, which have reduced death rates and restored the places we cherish.

He also discusses recent findings that temperatures have not warmed significantly in the past 15 years, which is not actually the case – rather several cooler years has reduced the rate of warming, as it has several times over the past decades of rapid warming. As EDF Vice President Nat Keohane recently wrote in response to this finding, this “underscores the fundamental nature of climate change — that we are creating dangerous uncertainties” and there are various explanations for this finding, notably that an unusual amount of heat has been stored in the deep ocean, rather than at the surface.

Chairman Smith also claimed that Hurricane Sandy was not caused by climate change. Scientists, including Kevin Trenberth of the National Center for Atmospheric Research, Bob Corell from the American Meteorological Society and Jeff Masters of Weather Underground and formerly of NOAA, confirm that Sandy’s damage was increased by rising seas, warming oceans, and was consistent with scientists’ climate predictions based on a warming artic. Just as we can’t say that steroids caused any one home run by Barry Bonds, steroids sure helped him hit more and hit them farther, and now climate change is increasing the likelihood of extreme of weather events, giving us weather on steroids.

Lastly Chairman Smith says that greenhouse gas regulations would hurt our economy. He does not account for the economic costs of inaction on climate change that many studies say outweigh the cost of action. Three of the most costly weather disasters in the US, Hurricanes Katrina and Sandy, and the 2012 Midwest drought, have happened in the past 6 years, costing $128 billion, $62 billion and $35 billion respectively. American taxpayers are footing a large portion of this cost including $12 billion from Sandy and $16 billion from Katrina under the National Flood Insurance Program, and $11 billion in crop insurance claims from the 2012 drought. These costs will only continue to increase as the effects of climate change become more apparent.

I appreciate that Chairman Smith is writing about climate change because it is a critical national debate. As chairman of the House Science Committee, however, he should start that discussion by acknowledging the most important and sound scientific facts: Climate change is real, it is caused by pollution from human activity, and it will become increasingly expensive for the US and the world.

Also posted in News, Science| 1 Response, comments now closed
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    Megan CeronskyMegan Ceronsky
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