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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.
Explaining climate change science & rebutting global warming misinformation
Scientific skepticism is healthy. Scientists should always challenge themselves to improve their understanding. Yet this isn't what happens with climate change denial. Skeptics vigorously criticise any evidence that supports man-made global warming and yet embrace any argument, op-ed, blog or study that purports to refute global warming. This website gets skeptical about global warming skepticism. Do their arguments have any scientific basis? What does the peer reviewed scientific literature say?
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This soil study has some deeply disturbing predictions about CO2 emissions
LightRocket via Getty Images
A new study published Thursday in the journal Science has determined that if organic carbon in deep layers of soil warms at a rate similar to surface layers it could result in a dramatic increase in carbon dioxide emissions by the end of the century, if not sooner.
According to research by scientists at the Department of Energy’s Lawrence Berkeley National Laboratory, deeper stores of carbon are more sensitive to warming than previously thought.
“Our calculations suggest that by 2100 the warming of deeper soil layers could cause a release of carbon to the atmosphere at a rate that is significantly higher than today, perhaps even as high as 30% of today’s human-caused annual carbon emissions depending on the assumptions on which the estimate is based,” said Caitlin Hicks Pries, a postdoctoral researcher in Berkeley Lab’s Climate and Ecosystem Sciences Division.
One of the largest sources of CO2 pollution from the average American consumer is the family car. The EPA states that 26% of greenhouse gas (GHG) emissions come from all forms of transportation (2014 figures). The largest source of GHG emissions, at 30%, is the electric power sector. However, just recently the Energy Information Administration (EIA) announced that transportation emissions have now surpassed those from electric power generation. Whatever the exact numbers, it's clear that if we want to reduce our GHG emissions we need to work to reduce them from these two sectors.
As individuals we can make choices which help decrease our electricity usage: LEDs over incandescent light bulbs, smart thermostats, etc. If we can afford it, and if we have the right house orientation, we can take an even bigger bite out of our CO2 emissions by installing solar PV panels to produce some or all of our electricity. But to get the biggest bang for our buck, perhaps the single best thing we can do to decrease our emissions is to switch from a normal car (internal combustion engine, or ICE, vehicle) to an all-electric vehicle (EV).
About two years ago my wife and I needed a second car and we decided to buy a 2013 Nissan Leaf. But because we live in Missouri, where most of the electric power is generated by coal, I was concerned that I would just be switching from ICE CO2 emissions to coal-electric emissions. Would we really be making any difference?
To answer that question (and others about how to compare MPG, fuel costs, etc. between a typical ICE and an EV) I kept track of data and made some calculations over a year-long period from September 2015 until August 2016. We bought the Leaf in June 2015 but it took me a few months to come up with a system and get a handle on what information I needed and where to find it.
Gasoline vs. Kilowatt-hours
We have a good grasp of what a gallon of gas means in terms of how much it costs and probably how many miles it will take us in our ICE cars. The "fuel" for an EV is kilowatt-hours (kWh) of electricity. Comprehending something as amorphous as a kWh stored in my Leaf's battery took a bit of a mental leap for me. The Leaf has a gauge on the instrument panel which displays the battery's amount of charge in 2 kWh increments, which isn't a very fine gauge. But the Leaf also records and uploads information on every trip made: kWh consumed, miles driven, etc. I can access this finer-detailed information from a Nissan website (figure 1). Now that I knew how many miles and how many kWh I used each month, I could look at my monthly electricity bills to see how much the EV "fuel" cost.
Figure 1. Portion of a screenshot of the Nissan Leaf website showing data for August 1, 2016. I travelled 25.1 miles and used 6.2 kWh. The "CO2 Savings" is not very accurate because it doesn't take into consideration the CO2 emissions from the electricity produced to power the car.
Knowing Twitter to be the prefered means of communication for the current POTUS and that he “may” have a thing or two to learn about climate science, John Mason recently set out to explain the carbon cycle in a series of 49 tweets in a language we hoped Donald Trump would be able to grasp.
As John explained: “I often wonder if a lot of climate change communication follows formats that may be unattractive to some people. Lengthy posts complete with explanatory graphics are appreciated by many, but others simply may not have the time to work through them for all sorts of reasons. Yet, this should not exclude them from accessing information. So regardless of whether Trump read the tweets or not, I wanted to proceed with this as an experiment in making climate communication available to a wider demographic. The simpler the framing of information, the more quickly it may be scanned and absorbed. I picked a fairly complex aspect of planetary science - Earth’s Carbon Cycle - and set out to simplify it whilst keeping it consistent with what the science says.
So, on February 28, the tweets started to go out on Twitter in a little tweet storm:
From heatwaves to hurricanes, working out the dollar cost of climate change is a tough task. Often used by policymakers to weigh up the costs and benefits of tackling rising emissions, the topic is not without controversy. A recent study suggesting that human-caused climate change brought benefits in the 20th century offers a good starting point to explore a few of the issues that surround this fraught, complex topic.
The research, published in the journal Public Library of Science, claims the world has experienced a “significant drop” in estimated climate impacts “since the late 1990s” and that the tendency for models to ignore natural fluctuations, not caused by greenhouse gases, could be “biasing the estimates”.
But climate scientists and economists that Carbon Brief spoke to say the study’s conclusions don’t stack up. What’s more, the paper’s odd use of outdated assumptions, old datasets and now-defunct models serve to muddy this already tricky-to-navigate subject.
The study uses a type of model that blends climate science and economics to retrospectively work out the cost of climate change in the 20th century. Known as Integrated Assessment Models (IAMs), these work by assigning monetary values to expected climate impacts at different levels of warming.
The authors use three different IAMs: DICE (Dynamic Integrated Climate-Economy model), developed by William Nordhaus, a professor of economics at Yale University; PAGE (Policy Analysis of the Greenhouse Effect model), developed by Chris Hope from the University of Cambridge; and FUND (Framework for Uncertainty, Negotiation and Distribution model), originally developed and now co-managed by Richard Tol, a professor at the University of Sussex and co-author on the new study.
Over time, all three models have been continually updated to reflect the evolving science on things such as climate sensitivity, adaptation, ice sheet melt and sea level rise. Despite the authors of the new paper stating that they employ “the most widely used IAMs”, they actually select outdated versions.
Agricultural wheeled irrigation sprinkling system in California Desert near a dirt road and a newly planted citrus grove. Credit: NicolasMcComber/iStock/Getty Images
The Yale Program on Climate Change Communication published the findings of its 2016 survey on American public opinion about climate change. The results are interesting – in some ways confusing – and yet they reveal surprisingly broad support for action to address climate change. The Yale team created a tool with which the results can be broken down by state, congressional district, or county to drill down into the geographic differences in Americans’ climate beliefs.
Acceptance of science despite confusion about expert consensus
The first survey questions asked about participants’ beliefs about whether climate change is happening, what’s causing it, what scientists think, and whether they trust climate scientists. Overall, 70% of Americans realize that global warming is happening, while just 12% said it’s not. A majority of Americans in every state answered the question correctly, ranging from 60% in West Virginia to 77% in New York and 84% in Washington DC. Drilling down to a more local level, majorities in every congressional district and nearly every county in America were aware of the reality of global warming.
But when asked whether most scientists think global warming is happening, Americans got a failing grade. Just 49% correctly answered ‘yes,’ while 28% believed there’s a lot of disagreement among scientists. In reality, even 95% of weathercasters – who are among the most doubtful groups of scientists about human-caused global warming – realize that climate change is happening. This shows that the campaign to cast doubt on the expert consensus on global warming has been remarkably successful in the US.
However, Americans trust climate scientists on the subject of global warming. Overall, 71% trust the scientific experts, while 26% distrust them. Majorities of Americans in every state, county, and congressional district trust climate scientists.
Regarding the cause of that global warming, only 53% of Americans correctly answered that it’s caused mostly by human activities, while 32% incorrectly said it’s mostly natural. By state, correct responses varied from 42% in Wyoming to 59% in California and 67% in Washington DC.
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Antarctic Sea Ice Sets Record Low, Providing Another Mystery for Scientists
Antarctica's Adelie penguins basked in a particularly warm summer in 2015 and now live amid shrinking sea ice. Credit: Getty Images
A new record warm temperature for Antarctica was confirmed by the World Meteorological Organization as sea ice surrounding the continent has shrunk to a record low.
The temperature reached its record high of 63.5 degrees Fahrenheit on March 24, 2015, according to an announcement by the WMO, which often takes years to verify new records.
The news came as sea ice around Antarctica is experiencing its lowest extent ever. As of March 1, only 820,000 square miles of the ocean around Antarctica was covered in ice, according to data from the National Snow and Ice Data Center in Boulder, Colo. The loss of ice represents an all-time minimum for Antarctic sea ice cover since satellite observations began in 1979.
The current decline, however, may not be part of a larger climate change trend. The low point comes less than three years after Antarctic sea ice set a record high in October 2014. "If you look at the long-term trend, Antarctic sea ice is still increasing slightly, said Son Nghiem, a researcher with NASA's Jet Propulsion Laboratory.
That increase has provided fodder for climate denial arguments and was a mystery to scientists because it differed so greatly from the rapid melting occurring in the Arctic. But recent research has provided clues to the reasons. The continent's unique topography shields it from warming occurring elsewhere, Nghiem said.
A study Nghiem and colleagues published last year found that topography creates icy winds blowing off Antarctica and a powerful ocean current that circles the continent. The study, published in the journal Remote Sensing of Environment, concluded that these two factors play a larger role in the formation and persistence of Antarctic sea ice than changes in temperature.
"I think Antarctic sea ice will be stable for at least some time into the future," Nghiem said.
That puts it in direct contrast with the Arctic, which is losing its ice at a rapid clip as it experiences a record-warm stretch and record low levels of sea ice at the North Pole. Last month temperatures in the far north were 20 degrees above normal according to data from the Danish Meteorological Institute. The ice cap over the North Pole receded to a record low in January for the second year in a row according to the National Snow and Ice Data Center.
In 2011 a bet was started up between "skeptics" of man-made climate change who follow Pierre Gosselin's "No Tricks Zone" blog, and myself and others here who follow SkS. It's a simple bet asking, "Will the next 2011-2020 decade be warmer than the previous 2001 – 2010 decade?" We're now over half way through this bet and here's where we stand.
What this graph represents is, what the state of the bet would be if it had been initiated 10 years ago, and ended this month. So, the red line represents the running decadal average to date. The yellow line represents the the running decadal line for the previous decade.
At no point in the past 7 years has the yellow line been above the red line, thus at no point during this bet has the previous decade been warmer than the current decade. In fact, at no point in the past 26 years has the decadal average been lower. The chosen data sets for the bet are an average of the UAH and RSS satellite data, which we now know have some challenges. But even with data that most benefits the cooler side of things, the decadal average temperature of every month of the entire past 6 years has been warmer than the previous decade. It was close 1-2 years ago, but still the current decade remained higher.
Since the start of the industrial revolution, humans have released hundreds of billions of tons of greenhouse gases into our atmosphere, acidifying oceans, increasing the frequency of extreme weather events, raising sea levels with the worst effects yet to come. The general consensus gleaned from the Paris Climate Summit in 2015 is that in order to halt the relentless march of climate change and its forecasted catastrophic consequences, one step we need to take is to transform our fossil fuel based economy to one powered by zero-emission renewable energy.
The good news is that investments in solar and wind generation have become competitive and in many cases cheaper and more profitable than similar investments in fossil fuels. The graphs below shows how solar and wind installations in the US have beaten fossil fuel installations for the past 3 years.
Globally, the conversation has shifted from “can renewables compete with fossil fuels?” to “how much intermittent renewable energy can our power grid handle?” Currently power grids rely on a steady and predictable stream of power generation. They can handle only so much of the fluctuation that comes from solar (surges during the day) and wind (surges when it’s windy).
The ‘social cost of carbon’ is an estimate of how much carbon pollution costs society via climate damages, and can also be considered the optimal carbon tax price. The US federal estimate ($37 per ton of carbon dioxide pollution) underpins at least 150 regulations across various federal agencies, and has thus become a prime target in the Trump administration’s efforts to roll back Obama’s climate policies.
Yesterday, the House Subcommittees on Environment and Oversight held a hearing on the social cost of carbon. The Republican Congressmen and their witnesses argued the federal estimate is too high, but a majority of economists think it’s too low. Not surprisingly, the Republican witnesses have been heavily funded by the fossil fuel industry. They made two main arguments: 1) that the $37 estimate should be based on domestic, not global climate impacts, and 2) that the government should have used a higher discount rate, which would result in a lower estimate.
Both arguments are entirely backwards.
Carbon pollution causes expensive global climate damages
The first argument, articulated by Chairman Andy Biggs (R-AZ), is an immoral one:
It is simply not right for Americans to be bearing the brunt of costs when the majority of benefits will be conferred away from home.
The “benefits” other countries would reap are effects like reducing the decimation of their crops by climate-fueled droughts. An accurate rephrasing of this statement would read: ‘It is simply not right for Americans pay for their carbon pollution when the majority of the costs and damages will be borne by poor people in third world countries.’ When framed accurately, it’s a completely unethical argument.
There seem to be a fair number of communications being sent to the White House right now. On Thursday 23rd February, The Hill reported that "Climate sceptics ask Trump to withdraw from UN agency". The "agency" in question being the U.N. Framework Convention on Climate Change and the name behind the letter being Richard Lindzen and some 300 of his buddies. This bunch of 300 signatories has something of a resemblance to those behind a January 2016 letter to NOAA, again with Lindzen involvement. Both lists read like a who's who of the usual suspects. Some sections could almost have been copied and pasted from the DeSmogBlog database of climate misinformers.
That aside, Lindzen and friends have missed an important point in this instance. Trump's preferred style of written communication is The Tweet. A series of long paragraphs is unlikely to garner the desired attention. Sometimes, it is necessary to communicate to people in their own language.
So let's try just that, in explaining to President Trump the importance of and the hazards associated with Earth's Carbon Cycle. Unlike Twitter though, this post reads in a user-friendly way, from top to bottom. So, without as much as a smidgen of FAKE NEWS, here we go:
@RealDonaldTrump 1/49
We want to tell you all about the Carbon Cycle. It helps make this planet great, so long as you don't MESS WITH IT.
@RealDonaldTrump 2/49
The Carbon Cycle is in two parts. One fast & one slow. They are different things because of the stuff they involve.
@RealDonaldTrump 3/49
The Fast Carbon Cycle involves plants. They feed on CO2 & make sugar. They keep it in their roots, stems and stuff.
If you read my articles regularly, you may have noticed multiple times I have stated that the scientific argument is over; there are no longer any reputablescientists that deny the overwhelming human influence in our climate. An open letter published last week by the anti-environmentalists proves my point.
If you read the headlines, it might have seemed impressive: “300 Scientists Tell Trump to Leave UN Climate Agreement.” Wow, 300 scientists. That’s a lot right? Actually, it’s a pitiful list.
First of all, hardly anyone on the list was a climate scientist; many were not even natural scientists. It is almost as though anyone with a college degree (and there are about 21 million enrolled in higher education programs just in the USA) was qualified to sign that letter.
Okay but what about the signers of the letter? Surely they are experts in the field? Not so much. It was very difficult to find the list of signers online however I was able to acquire it with some help. See for yourself - Google “300 scientists letter climate change” in the past week. You will see many stories in the press, but try finding the actual letter or the list of names. The version I obtained was dated February 23, 2017 which helps narrow your searching. In an era of Dr. Google, it is unbelievable that the letter itself was not made more available.
Okay but let’s get to the central issue. These 300 scientists must be pretty good at climate science, right? Well let’s just go through the list, alphabetically. Here is a sampling (text copied verbatim from the version of the letter I obtained).
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Demonstrators rally for science near the AAAS annual meeting in Boston in February.
The March for Science, set for 22 April, is creating a buzz in the scientific community. The march arose as a grassroots reaction to concerns about the conduct of science under President Donald Trump. And it has spurred debate over whether it will help boost public support for research, or make scientists look like another special interest group, adding to political polarization.
Leaders of many scientific societies have been mulling whether to formally endorse or take a role in the event. And today, some major groups—including AAAS (publisher of ScienceInsider), which has about 100,000 members, and the American Geophysical Union (AGU), which has about 60,000 members—announced they are signing on. The two organizations were on a list of 25 formal partners unveiled by the March for Science.
“We see the activities collectively known as the March as a unique opportunity to communicate the importance, value and beauty of science,” AAAS CEO Rush Holt wrote in a statement on the website of the Washington, D.C.–based organization, which bills itself as the largest general science society in the world. Participation “is in keeping with AAAS’ long-standing mission to ‘advance science, engineering and innovation throughout the world for the benefit of all people.'”
If you meet a group of climate scientists, and ask them how much sea levels will rise by say the year 2100, you will get a wide range of answers. But, those with most expertise in sea level rise will tell you perhaps 1 meter (a little over three feet). Then, they will immediately say, “but there is a lot of uncertainty on this estimate.” It doesn’t mean they aren’t certain there will be sea level rise – that is guaranteed as we add more heat in the oceans. Here, uncertainty means it could be a lot more or a little less.
Why are scientists not certain about how much the sea level will rise? Because there are processes that are occurring that have the potential for causing huge sea level rise, but we’re uncertain about how fast they will occur. Specifically, two very large sheets of ice sit atop Greenland and Antarctica. If those sheets melt, sea levels will rise hundreds of feet.
Parts of the ice sheets are melting, but how much will melt and how fast will the melting occur? Are we talking decades? Centuries? Millennia? Scientists really want to know the answer to this question. Not only is it interesting scientifically, but it has huge impacts on coastal planning.
One reason the answer to this question is illusive is that melting of ice sheets can occur from above (warm air and sunlight) or from below (warm ocean waters). In many instances, it’s the melting from below that is most significant – but this melting from below is really hard to measure.
With hope we will have a much clearer sense of ice sheet melting and sea level rise because of a new scientific endeavor that is part of a NASA project - Oceans Melting Greenland (OMG). This project has brought together some of the best oceanographers and ice experts in the world. The preliminary results are encouraging and are discussed in two recent publications here and here.
In the papers, the authors note that Greenland ice loss has increased substantially in recent decades. It now contributes approximately 1/3 to total sea level rise. The authors want to know whether this contribution will change over time and they recognize that underwater processes may be the most important to study. In fact, they note in their paper:
We have a message for Pruitt: We are scientists, and we are not going away. And neither is climate change.
IN May, Scott Pruitt wrote an article suggesting that protecting the environment and its people are examples of government overreach. Now, Pruitt is head of the Environmental Protection Agency, a federal agency whose mission is “to protect human health and the environment.”
We challenge Pruitt to take this mission seriously and reconsider his public statements on science, climate change and our national need for environmental protection. We have a message for Pruitt: We are scientists and we are not going away. And neither is climate change.
Pruitt has claimed that “healthy debate is the lifeblood of American democracy.” We agree. In fact, the scientific enterprise is built on debate, along with skepticism, conflict and progress. But do you know what we do not debate anymore? Basic physical science — like the fact that Earth’s climate is changing, or like the fact that the planet spins in a certain direction, or that the ocean’s tides are influenced by the moon. As a scientific community, we have immense consensus on these issues.
A month into his presidency, Donald Trump already has a minus-8 job approval rating (43% approve, 51% disapprove). Congress has a minus-50 approval rating, and the Republican Party has a minus-14 favorability rating. All are facing widespread protests, marches, and public resistance. Hundreds of concerned constituents have been showing up to town hall events held by Republican Congressmen, like this one with Tom McClintock (R-CA):
His constituents asked McClintock about the current hot-button issues: repealing Obamacare, the border wall, the Muslim ban, and climate change.
The first three topics have strong support from the Republican base, but they’re unpopular among most of the rest of Americans. That’s why Trump’s approval is held afloat by Republican support (about 85% approve), while only 35% of independents and fewer than 10% of Democrats view him favorably. In fact, they view these policies so unfavorably that there are constant mass protests. And then there’s this:
Betting markets think the odds are better that Trump won't last the year than that he'll be re-elected
Trump and the Republican Party need an issue and a policy that has strong support among all Americans. Climate change and a carbon tax fit the bill perfectly.
Americans - including Republicans - support climate solutions
69% of Americans - including about half of Trump voters - think the US should participate in the Paris climate agreement.
80% of Americans - including 62% of Trump voters - agree that the US should regulate and/or tax carbon pollution. More Trump voters support doing both (31%) than doing neither (21%).
66% of Americans support a carbon tax, as do about half of Trump voters.
81% of Americans - including 73% of Trump voters - think the country should use more renewable energy.
55% Americans - including 33% of Trump voters - think we should use less fossil fuels than we do today. Only 31% of Trump voters think we should use more fossil fuels.
Models long have been targeted as a weak link by those steadfastly refusing to accept mainstream climate science.
But a review of their actual performance paints a different picture.
This month’s original “This is Not Cool” video by independent videographer Peter Sinclair offers strong evidence supporting the value of climate models in helping forecast global warming. He weaves together a string of archival televised presentations, classroom lectures, congressional testimony, and one-on-one interviews in relating how climate models frequently have provided valuable insights into coming developments only later seen by direct observation.
It will come as no great surprise to the professional climate modeling community, but the testimonials in the video suggest that those dismissive of the mainstream climate science may have to find a new target for their barbs.
Sinclair in the video uses his familiar blend of new and decades-old footage to document numerous important cases in which climate models called things right, ranging from the “whole warming of the earth that’s occurred over the last few decades” to the more rapid warming of the Arctic and of continental interior regions, and faster warming of night than of daytime.
The evacuation of nearly 200,000 people near Oroville Dam is the kind of event that makes climate change personal. A co-worker of mine was forced out of his home for several days by the emergency evacuation, and another friend was visiting Lake Oroville and happened to leave 15 minutes before the evacuation order was issued.
Like many extreme events, the Oroville emergency is a combination of natural weather likely intensified by climate change. California regularly sees “atmospheric rivers” that deluge the state with rainfall, but in a hotter world, scientists anticipate that they’ll be amplified by an increase in the amount of water vapor in the atmosphere.
Northern California is in the midst of its wettest rainy season on record – twice as wet as the 20th century average, and 35% wetter than the previous record year. It proved to be almost too much for America’s tallest dam to handle. Water managers were forced to use Oroville Dam’s emergency spillway for the first time ever, which then began to erode, posing the threat of a failure and catastrophic flooding of nearby towns.
Northern California Sierra precipitation - average, previous wettest year, and 2016-2017. Illustration: California Department of Water Resources
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