Selected category: Basic Science of Global Warming

Scott Pruitt’s Misleading Senate Testimony – Will ‘Alternative Science’ Replace Real Science at EPA?

Earth as seen from a NOAA weather satellite. Photo: NOAA/NASA

As a climate scientist who is trained to base his conclusions strictly on scientific evidence and not politics, I find it particularly troubling that Scott Pruitt, President Trump’s pick to head the U.S. Environmental Protection Agency (EPA), is misrepresenting the scientific data that shows the earth’s atmosphere is warming.

Pruitt hopes to run the agency responsible for protecting the lives and health of Americans from environmental threats, and that includes reducing greenhouse gas emissions that are warming the planet. And as the Supreme Court has ruled, EPA has the authority to address greenhouse gases.

However, in his testimony before the Senate Environment and Public Works Committee on January 18, and then in follow-up written answers to Senators, Pruitt made several misleading, or flat-out inaccurate, statements.

In his attempt at subterfuge, Pruitt leaned on false and misleading climate-skeptic myths that have been debunked time and time again.

For instance, consider this one question and answer:

Written question from Sen. Jeff Merkley: Are you aware that each of the past three decades has been warmer than the one before, and warmer than all the previous decades since record keeping began in the 1880s? This trend is based on actual temperature measurements. Do you believe that there is uncertainty in this warming trend that has been directly measured? If so, please explain.

Written answer from Scott Pruitt: I am aware of a diverse range of conclusions regarding global temperatures, including that over the past two decades satellite data indicates there has been a leveling off of warming, which some scientists refer to as the "hiatus." I am also aware that the discrepancy between land-based temperature stations and satellite temperature stations can be attributed to expansive urbanization within in our country where artificial substances such as asphalt can interfere with the accuracy of land-based temperature stations and that the agencies charged with keeping the data do not accurately account for this type of interference. I am also aware that 'warmest year ever' claims from NASA and NOAA are based on minimal temperature differences that fall within the margin of error. Finally, I am aware that temperatures have been changing for millions of years that predate the relatively short modern record keeping efforts that began in 1880. (Questions for the Record, page 145)

In response to the scientific evidence that the last three decades have each been warmer than the one before it, Mr. Pruitt offered negligent claims that both the satellite data and surface based observations have shown there to be no warming over the last two decades – the so-called global warming hiatus.

Science does not agree with this assessment.

The idea of a hiatus and a potential discrepancy between satellite and surface based data have been under intense objective scrutiny by the scientific community for some time – and the results are in:

  • NOAA scientists recently published a peer reviewed article in the Journal Science that clearly shows the “hiatus” to have never existed.
  • Then last month a follow up study, undertaken by a separate group of researchers as an objective check on the NOAA result, also confirmed that the global warming hiatus never happened.
  • Additionally, the alleged satellite discrepancy has also been debunked – its origin an artifact of necessary, but potentially faulty, post-processing techniques that are employed when using data gathered by a satellite from space, as opposed to direct surface temperature measurements from thermometers. Stated plainly, raw satellite observations from space are not as accurate as those taken in the actual location, so these raw observations need to be quality controlled for scientific accuracy.

Next, in the same answer, in what can only be described as countering his own misguided narrative, Pruitt attempted to blame the increasing temperature trend – which he just stated did not exist via the hiatus argument – on an unfounded discrepancy between satellite based and urban land based data.He claimed the increase in urbanization was causing a fictitious rise in global temperature – an impact long shown to be minimal at best, especially when applied to the massive geographic expanse of the world relative to the lesser change in the geographic extent of cities.

Pruitt went on to quibble with the fact that 2016 was the warmest year ever recorded, by overemphasizing the role of negligible differences in how various scientific agencies around the world calculate the globally averaged temperature.

Actually, the diversity of approaches is a scientific strength, because it provides a balanced view of the data – much like seeking a second opinion on a medical diagnosis. It's vital to note that despite these trivial differences in methodology, the three long-running analyses by NASA, NOAA, and Great Britain’s UK Met Office all showed 2014 to 2016 to be the three consecutive warmest years on record. This fact is indisputable.

Pruitt concluded his misdirection by pointing out his awareness that temperatures have been changing for millions of years, and predating the relatively short modern record. Mr. Pruitt is indeed correct that the rapid warming in recent decades is quite alarming in the context of the much slower and longer term natural changes – although I don’t think that was what he was trying to say.

Pruitt seemed unaware of the latest scientific evidence on the various topics he chose to explore during his testimony. That indicates an ignorance of science coupled with a lack of preparation which adds up to being unfit to lead a scientifically-based government agency.

Also posted in Greenhouse Gas Emissions, News, Policy, Science, Setting the Facts Straight| Read 3 Responses

Hurricane Matthew And Climate Change: What We Know So Far

Image source: NASA

Hurricane Matthew. Image source: NASA

As I write this, Hurricane Matthew is battering the Atlantic coast of Florida, having wreaked havoc on Haiti and the Bahamas. In Haiti hundreds lost their lives due to the Hurricane’s destructive winds and storm surge.

With half a million Floridians already without power even before Matthew makes landfall, there is sure to be significant damage in Florida and other portions of the southeast U.S. from this Category 3 storm, the first major hurricane to strike the U.S. since Wilma in 2005. Our first and highest priority is to help the victims and others in the path of the storm.

However, as with any destructive weather event, people are asking about the role of climate change.

We know that increases in sea level caused by climate change result in higher and more destructive storm surges, like the one that swamped lower Manhattan during Superstorm Sandy in 2012. Coastal towns suffer greater damage because the ocean starts out higher, and the storm shoves more water inland. Coastal states like South Carolina and Florida – and the rest of us through taxes and insurance rates – will pay billions as a result.

But what about the connection between climate change and the strength of hurricanes themselves?

Hurricanes are fueled by the warm waters of the tropical oceans, which have been warming as the result of increased emissions of greenhouse gases.

However, hurricanes are also impacted by wind shear – the change of wind speed and direction with height. For a hurricane to grow and strengthen it needs a low wind shear environment, and some research indicates that climate change may actually increase wind shear over the tropical Atlantic. And that’s the rub. When it comes to climate change and hurricanes, the warming oceans and increasing wind shear are in competition. Science is still working out which mechanism will dominate as the global climate continues to warm – so stay tuned.

But there is more to the story than just the relationship between the intensity or frequency of hurricane and global warming. Because the climate system is so complex, no storm happens in a vacuum. Scientists have been working on the issue of “attribution”— How much can we know about the link between specific storms and climate change? The organization Climate Central has also been working intensively in this area.

While we await attribution studies, we shouldn’t lose site of the bigger picture: we already know that climate change is doing tremendous damage to our environment and our economy. Citibank estimates the cost of inaction on climate change is in the trillions. So let’s first help those hurt by this storm, then focus on cutting the pollution that is causing so much damage to our world.

Also posted in Extreme Weather, Greenhouse Gas Emissions, Oceans, Science| Comments are closed

The Impacts of Climate Change on Human Health – a Sobering New Report

We have even more information this week about the ways climate change poses a threat to human health.

The U.S. Global Change Research Program just released its newest report—The Impacts of Climate Change on Human Health in the United States. This scientific assessment is the culmination of three years of work by hundreds of experts, and builds on the more general National Climate Assessment released in 2014.

The report concludes that every American is vulnerable to the health impacts associated with climate change.

Health Threats from Climate Change graphic

Graphic created by Ilissa Ocko, EDF Scientist

Scientists have known for decades that climate change threatens human health via excessive heat, worsened air quality, water related illnesses, food safety, diseases transmitted by pests like fleas and mosquitos, and mental stress. The new report thoroughly characterizes our current understanding of these impacts.

Because scientific understanding has advanced significantly in recent years, the authors also reviewed new information and insights from several recent scientific, peer-reviewed publications and other publicly available resources.

For example, new data revealed that the Ragweed season has grown by as much as 27 days in the central U.S. from 1995 to 2011, and the incidence of Lyme disease in the Northeast has doubled from 2001 to 2014, both consistent with warming trends.

Recent modeling studies have also improved quantification estimates of and confidence in projected health outcomes from climate change. By midcentury, scientists project that there will be as many as thousands of additional ground-level ozone (smog) related illnesses and premature deaths, and the majority of the western U.S. will have a 500 percent  increase in the number of weeks with risk of very large fires. By the end of the century, scientists project that there will be an additional 27,000 summertime heat-related deaths annually in over 200 U.S. cities (that are currently home to 160 million people), and harmful toxin-producing algal blooms could develop up to two months earlier and persist for up to two months longer.

Through climate and weather changes and disruptions to ecosystems and societal systems, here are the main concerns about climate change impacts on human health:

  • Temperature Related Death and Illness — Future climate warming could cause up to tens of thousands of additional deaths each year from heat in the summer, from loss of ability to control internal temperature, and worsened chronic cardiovascular and respiratory diseases
  • Air Quality Impacts — The future could include limited productivity at work and school due to exacerbated ground-level ozone (smog) health impacts from modified weather patterns conducive to ozone formation, and worsened allergy and asthma conditions from more airborne pollen and longer pollen seasons
  • Vectorborne Disease — The seasonality, distribution, and prevalence of vectorborne diseases, including Lyme disease and West Nile virus,  may change with changing temperature and rainfall patterns due to altered geographic and seasonal distributions of mosquitoes, ticks, and fleas
  • Water-Related Illness — Risk of exposure to illnesses increases as the growth, survival, spread, and toxicity of water-related pathogens and toxins is impacted by temperature and extreme rainfall events, and aging water infrastructure is vulnerable to failure with extreme events and storm surges
  • Food Safety, Nutrition, and Distribution — Rising temperatures, changing weather patterns, and extreme events have consequences for contamination, spoilage, and the disruption of food distribution, whereas higher carbon dioxide levels lower nutritional value of crops despite boosting plant growth
  • Extreme Weather — Fatalities, injuries, and infrastructure damages are imminent with increases in the frequency and/or intensity of extreme precipitation, hurricanes, coastal inundation, drought, and wildfires
  • Mental Health and Well-Being — Mental health conditions may develop with exposure to disasters or worsen by extreme health

Overall, the report is a sobering portrait of the risks we face because of climate change — and it underscores the urgency for climate action.




Also posted in Extreme Weather, Health, News, Plants & Animals, Science| Comments are closed

Climate denial has no place in the court

(This post was co-written by EDF’s Martha Roberts and Ilissa Ocko)

As federal courts consider the legal merits of the U.S. Environmental Protection Agency’s (EPA) Clean Power Plan — America’s first-ever national limits on carbon pollution from power plants – we find ourselves in a situation that might have felt familiar to Galileo, who was hauled before authorities for having the temerity to make conclusions based on science.

Three hundred seventy-four years after Galileo, flat-earth Clean Power Plan opponents are using the court’s time to challenge EPA’s rock solid conclusions about the scientific realities of climate change. They’re using misinformation and misrepresentation in an attempt to block EPA’s flexible and efficient approach to reducing the carbon pollution that is causing so much costly damage to our society.

Yes, they’re still doing that in 2016.

The Usual Suspects

The latest assault takes the form of an amicus, or “friend of the court,” brief that was submitted last week to the U.S. Court of Appeals for the D.C. Circuit. It deploys selective reasoning and misleading arguments in an attempt to discredit evidence of climate change.

It’s numbingly familiar, but not surprising, to see Fred Singer’s name on the brief. A former tobacco industry mouthpiece, he’s been a mainstay for years in what’s been called the “parallel universe” of climate denial conferences.

It’s also no surprise that Peabody Energy — the world’s largest privately owned coal company — contested EPA’s rock solid climate science in an earlier submission to the court, given the company’s history of obfuscating the impacts of climate change in order to protect its profits.

The Real Motivation

This effort isn’t about debating science. It’s about using misinformation to obstruct climate progress. This attack is part of a longstanding effort to undermine EPA’s common sense solutions to limit harmful greenhouse gas pollution at all – despite that fact that the Supreme Court has repeatedly ruled that the Clean Air Act requires EPA to address climate pollution. Coal companies and their hired allies have relentlessly attacked EPA’s safeguards to protect human health and the environment from climate pollution.

Junk Science Amicus Brief

This junk science submission, authored by Singer and others, claims to be based on “real world empirical temperature data” (amicus brief, page 15) – but in truth it’s deceptively unscientific, cherry-picking dates and locations in an effort to rebut overwhelming evidence of rising surface temperatures.

Two obvious flaws demonstrate the problematic reasoning employed by the brief.

First, the authors contend that globally averaged surface temperature has not increased because:

The decade of the 1930s still has the most currently held high-temperature records for States within the United States. (amicus brief, page 31)

This point suffers from cherry picking data that seems to support their phony argument. Drawing a comparison between a long term globally averaged temperature trend (i.e., as related to anthropogenic climate change) and summertime regional temperature spikes in a select portion of the U.S. is inherently misleading (see Figure 1 below). The U.S. covers only two percent of the global surface area, and the Great Plains far less. Arguing that a small regional temperature anomaly undermines for the global temperature trend is scientifically untenable.

Figure 1: How Cherry-Picked Data Misrepresents the Larger Picture

Source: The U.S. Global Historical Climatology Network Dataset

Source: The U.S. Global Historical Climatology Network Dataset

The second flaw is an egregious error with respect to defining a linear trend. The authors break the temperature time series in half and display two distinct trend lines separated by a large step increase, as opposed to the scientifically appropriate approach of employing the entire time series to define a trend.

Figure 2. The Amicus Brief’s Broken Time Trend Global Average Temperature Anomalies

(amicus brief, page 7)

They do this to hide the trend. It’s a classic strategy used by the climate denial community to deny trends, known as the “escalator” (see Figure 3 below).

The authors argue that the absence of a trend in the latter portion of the record indicates a lack of evidence for an anthropogenic climate change signal during this time. However, their starting point for the latter half is during the 1997-1998 El Nino, one of the strongest such events on record. Given that El Nino has a significant warming influence on a given year’s global temperature, starting at this point in the record introduces a strong temperature bias — i.e. the authors purposely choose a starting point with an extremely high temperature in order to create the appearance of a plateau in the years that follow.

It’s a bit like beginning a chart of Barry Bonds’ home runs per season in 2001, when he hit 73. The authors fail to disclose that the globally averaged temperature exceeded the 1990’s average in every year of the first decade of the 21st century and that both 2014 and 2015 broke records as the hottest years ever recorded — further confirming their selection bias.

Figure 3: The Escalator — An Example of How One Can Manipulate a Trendline to Pretend That There Is No Trend

 escalator graphic


The brief also attempts to reject EPA’s conclusion that the atmosphere in the tropics warms faster than the surface as a response to rising carbon dioxide levels.

The brief presents data from only a single location in an attempt to rebut this conclusion — the tropical central and eastern Pacific Ocean, an area home to the El Nino Southern Oscillation (ENSO), the largest mode of natural interannual climate variability on the planet.

Using only one region (and in this case a single idiosyncratic point) to represent the entire global tropics is highly misleading and scientifically inappropriate. The data manifestly suffer from selection bias and are not representative of the full population of tropical climate data.

Indeed, the temperature time series shown in their analysis correlate extremely well with recently observed El Nino and La Nina events — suggesting that their index is simply a proxy for the El Nino/La Nina signal. Extracting a trend from an area with extremely large natural variability is inherently tenuous, because the large background variability swamps our ability to observe any other data trends.

Unfortunately, this is not the first time opponents have inaccurately distorted climate data in this case.

Earlier in this same crucial case, Peabody represented to the court that EPA’s claims of climate harms "substantially outrun the available evidence." (brief, page 7 footnotes)

Peabody’s efforts to justify these misleading allegations misrepresent scientific understanding of climate science in several major respects. Two core inconsistencies, among several, include:

  • Peabody’s biased assertion of hiatus in warming since 1998 — as mentioned earlier, beginning a trendline in 1998, an exceptionally warm year due to an unusually strong El Nino, is nonsensical and irrelevant to the long-term trend. Further, surface air temperatures are certainly still increasing. The 2000s were warmer than the 1990s, 2015 smashed all previous surface air temperature records, and heat uptake in the ocean has doubled over the last 20 years.
  • Flawed reasoning that increasing Antarctic sea ice disproves climate change — Antarctic sea ice is influenced by differences in fresh water supply and circulation in the Southern Ocean. Land ice that has taken thousands of years to accumulate in Antarctica is melting at a rapid rate due to warmer temperatures, changing the chemistry of the water and likely preventing the buildup of sea ice. Peabody’s submission ignored and omitted this crucial context.

Sadly, it’s not really news that Peabody is presenting misleading climate information. Peabody, the largest private-sector coal company in the world, was cited last fall by the New York Attorney General for violating investor protection laws by misrepresenting climate risk in its corporate filings. The Attorney General noted that Peabody “repeatedly denied in public financial filings to the Securities and Exchange Commission that it had the ability to predict the impact that potential regulation of climate change pollution would have on its business, even though Peabody and its consultants actually made projections that such regulation would have severe impacts on the company.”

Also posted in Clean Air Act, Clean Power Plan, EPA litgation, Policy, Science, Setting the Facts Straight| Comments are closed

Climate Change and Millennials – An Entire Lifetime of Warmer Than Average Temperatures

While reading the announcement that 2015 had broken – indeed, shattered – the hottest year on record set by 2014, there was one fact that really made things personal: we have now had 31 straight years since a single month was cooler than the twentieth century global average temperature. That means that I have never lived through a month that wasn’t warmer than average – never once in my lifetime.

My entire career as a climate scientist is focused on reducing the threat of global warming, and yet I have never even been alive at a time when the climate was stable. I technically don’t even know what normal is.

Warmest Years on Record graphic

So on one hand, you could say that I don’t even know what I am fighting for. On the other hand, I’ve been afforded two unique opportunities because I’ve lived in the shadow of global warming my entire life.

First, because I’ve grown up at a time when heat records are broken over and over again, I was aware of this worldwide crisis during those impressionable and important “pick a major” years of college. I was thus able to set myself on a career path shaped by climate change from the get-go, rather than later on in life once I was already an established professional in something else.

Second, because my elder colleagues have already identified – with extreme confidence – that humans are the main cause of climate change, I’ve been able to focus on solutions from the get-go, and not just causes and impacts. I have thus benefitted from previous scientific research because I could explore avenues to address climate change, because if humans are the cause, then we are also the solution.

And it’s not just me; there is now an entire generation of young people motivated and empowered to do something about climate change. We – almost the entire millennial generation – have never lived in a world without global warming.

Perhaps for similar reasons to mine (and/or because we think we’re special), my generation has shown a propensity for not just caring about climate change, but doing something about it. Whether on their campuses of their schools or the communities where they live, my generation is showing that they want solutions. In fact, eighty-percent of millennials support cleaner energy in the U.S., regardless of party affiliation.

For this reason among others, I am more hopeful about our future than ever before. Climate change has been impacting my generation our whole lives, but it doesn’t have to stay that way. We didn’t ask for this challenge, but I truly believe we’ll be able to rise up to meet it.

Also posted in Extreme Weather, Greenhouse Gas Emissions, News, Science| Read 1 Response

Defending Our Future: Fighting Climate Change in South Florida

Speakers at the Defend Our Future/Voto Latino event: (back row) Alexis Calatayud, FIU Student Body President; Eric Chappell, Climate Corp alum; Edwin Luevanos, Citizen Energy; Mustafa Santiago Ali, EPA; (front row) Enrique Acevedo, Univision; Karina Castillo, CLEO Institute/MCAF

Speakers at the Defend Our Future/Voto Latino event: (back row) Alexis Calatayud, FIU Student Body President; Eric Chappell, Climate Corp alum; Edwin Luevanos, Citizen Energy; Mustafa Santiago Ali, EPA; (front row) Enrique Acevedo, Univision; Karina Castillo, CLEO Institute/MCAF

On Tuesday night Defend Our Future, EDF’s initiative to empower young people to fight climate change, partnered with Voto Latino, an organization that empowers Latino Millennials to claim a better future for themselves and their community, to bring a Power Summit “Pop Up” to Florida International University (FIU). We brought together 100 area youth leaders to engage in an evening of conversation focused on how young Latinos can fight climate change in South Florida. In Miami, in particular, addressing climate change is a critical part of this equation, and seeing a room full of rising leaders ready to take action was inspiring.

To kick off the conversation, Environmental Protection Agency (EPA) Senior Advisor on Environmental Justice, Mustafa Santiago Ali, reminded the crowd:

We need to be laser-focused on climate change.

He shared his story about growing up near a power plant in West Virginia, and reminded us about the importance of protecting our communities from the interconnected threats of air pollution and climate change. This is especially true, Ali said, for Latinos and African-Americans because climate change can compound other serious threats to our health and well-being. Read More »

Also posted in Latino partnerships, Partners for Change, Science| Comments are closed
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