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?
New scenarios show how the world could limit warming to 1.5C in 2100
Posted on 13 March 2018 by Zeke Hausfather
This is a re-post from Carbon Brief
In the 2015 Paris Agreement on climate change, nearly every country on Earth pledged to keeping global temperatures “well below” 2C above pre-industrial levels and to “pursue efforts to limit the temperature increase even further to 1.5C”.
However, at the time, scientists had only modelled energy system and carbon mitigation pathways to achieve the 2C target. Few studies had examined how the world might limit warming to 1.5C.
Now a paper in Nature Climate Change presents the results from a new modelling exercise using six different “integrated assessment models” (IAMs) to limit global temperatures in 2100 to below 1.5C.
The results suggest that 1.5C is achievable if global emissions peak in the next few years and massive amounts of carbon are sucked out of the atmosphere in the second half of the century through a proposed technology known as bioenergy with carbon capture and storage (BECCS).
Burning coal may have caused Earth’s worst mass extinction
Posted on 12 March 2018 by dana1981
Earth has so far gone through five mass extinction events – scientists are worried we’re on course to trigger a sixth – and the deadliest one happened 252 million years ago at the end of the Permian geologic period. In this event, coined “the Great Dying,” over 90% of marine species and 70% of terrestrial vertebrate species went extinct. It took about 10 million years for life on Earth to recover from this catastrophic event.
Scientists have proposed a number of possible culprits responsible for this mass extinction, including an asteroid impact, mercury poisoning, a collapse of the ozone layer, and acid rain. Heavy volcanic activity in Siberia was suspected to play a key role in the end-Permian event.
Recently, geologist Dr Benjamin Burger identified a rock layer in Utah that he believed might have formed during the Permian and subsequent Triassic period that could shed light on the cause of the Great Dying.
Sheep Creek Valley, Utah. Photograph: Benjamin Burger
During the Permian, Earth’s continents were still combined as one Pangea, and modern day Utah was on the supercontinent’s west coast. Samples from the end-Permian have been collected from rock layers in Asia, near the volcanic eruptions, but Utah was on the other side of Pangaea. Burger’s samples could thus provide a unique perspective of what was happening on the other side of the world from the eruptions. Burger collected and analyzed samples from the rock layer, and documented the whole process in a fascinating video:
2018 SkS Weekly Climate Change & Global Warming Digest #10
Posted on 11 March 2018 by John Hartz
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This mind-boggling study shows just how massive sea level rise really is
A satellite view of Antarctica is seen in an undated NASA photo released on Feb. 6, 2012. (Reuters/NASA)
As our planet continues to warm, coastlines worldwide will retreat inland — in the long run, maybe by a lot. That means some coastal cities, in places like Florida — where Hillary Clinton and Bernie Sanders debated precisely this topic on Wednesday night — stand to lose quite a lot of land where people currently live and own property.
It seems doubtful that we can defend all of the many coastal zones that will be at risk. So is there any other way to head off sea level rise?
It may sound ridiculous to even contemplate. But in a new study just out in the open access journal Earth System Dynamics, scientists have actually published an idea for doing that and provided some calculations regarding the scale of what it would take. That scale turns out to be simply massive, ultimately rendering the idea about as unfathomable as the oceans themselves.
This mind-boggling study shows just how massive sea level rise really is by Chris Mooney, Energy & Environment, Washington Post, Mar 10, 2016
2018 SkS Weekly Climate Change & Global Warming News Roundup #10
Posted on 10 March 2018 by John Hartz
A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week.
Climate change threatens ability of insurers to manage risk
Extreme weather is driving up uninsured losses and insurers must use investments to fund global warming resilience, says study
Severe flooding in Carlisle, north-west England, December 2015. Photograph: Andrew Yates/Reuters
The ability of the global insurance industry to manage society’s risks is being threatened by climate change, according to a new report.
The report finds that more frequent extreme weather events are driving up uninsured losses and making some assets uninsurable.
The analysis, by a coalition of the world’s biggest insurers, concluded that the “protection gap” – the difference between the costs of natural disasters and the amount insured – has quadrupled to $100bn (£79bn) a year since the 1980s.
Mark Carney, the governor of the Bank of England, warns in the new report that: “Over time, the adverse effects of climate change could threaten economic resilience and financial stability [and] insurers are currently at the forefront.”
The ClimateWise coalition of 29 insurers, including Allianz, Aon, Aviva, Lloyd’s, Prudential, Swiss Re and Zurich, conclude that the industry must use more of its $30tn of investments to help fund increased resilience of society to floods, storms and heatwaves.
Climate change threatens ability of insurers to manage risk by Damian Carrington, Climate, Guardian, Dec 7, 2016
New research, February 26 - March 4, 2018
Posted on 9 March 2018 by Ari Jokimäki
A selection of new climate related research articles is shown below.
The figure is from paper #57.
Climate change mitigation
1. How modifications of China's energy data affect carbon mitigation targets
"After revision, China's mitigation challenges increase by 5%."
2. The contribution of sectoral climate change mitigation options to national targets: a quantitative assessment of dairy production in Kenya
3. An optimal mix of conventional power systems in the presence of renewable energy: A new design for the German electricity market
4. Effect of major policy disruptions in energy system transition: Case Finland
5. Intermediaries’ perspectives on the public’s role in the energy transitions needed to deliver UK climate change policy goals
Jet fuel from sugarcane? It’s not a flight of fancy
Posted on 8 March 2018 by Guest Author
by Deepak Kumar, Postdoctoral Researcher, University of Illinois at Urbana-Champaign; Stephen P. Long, Professor of Crop Sciences and Plant Biology, University of Illinois at Urbana-Champaign, and Vijay Singh, Professor of Agricultural and Biological Engineering and Director of Integrated Bioprocessing Research Laboratory, University of Illinois at Urbana-Champaign
This article was originally published on The Conversation. Read the original article.
The aviation industry produces 2 percent of global human-induced carbon dioxide emissions. This share may seem relatively small – for perspective, electricity generation and home heating account for more than 40 percent – but aviation is one of the world’s fastest-growing greenhouse gas sources. Demand for air travel is projected to double in the next 20 years.
Airlines are under pressure to reduce their carbon emissions, and are highly vulnerable to global oil price fluctuations. These challenges have spurred strong interest in biomass-derived jet fuels. Bio-jet fuel can be produced from various plant materials, including oil crops, sugar crops, starchy plants and lignocellulosic biomass, through various chemical and biological routes. However, the technologies to convert oil to jet fuel are at a more advanced stage of development and yield higher energy efficiency than other sources.
We are engineering sugarcane, the most productive plant in the world, to produce oil that can be turned into bio-jet fuel. In a recent study, we found that use of this engineered sugarcane could yield more than 2,500 liters of bio-jet fuel per acre of land. In simple terms, this means that a Boeing 747 could fly for 10 hours on bio-jet fuel produced on just 54 acres of land. Compared to two competing plant sources, soybeans and jatropha, lipidcane would produce about 15 and 13 times as much jet fuel per unit of land, respectively.
Explainer: The polar vortex, climate change and the ‘Beast from the East’
Posted on 7 March 2018 by Guest Author
This is a re-post from Carbon Brief by Robert McSweeney
While much of Europe is shivering in subzero temperatures, the Arctic and eastern US have basked in unseasonably warm conditions in recent weeks.
Arctic temperatures during February hit record highs, including nine separate days where temperatures were above zero. This is more than 30C warmer than expected for an Arctic winter.
Numerous news reports have pointed the finger at the “polar vortex” for this unusual combination of weather extremes. Some have suggested that climate change is making these events more likely, driven by declining Arctic sea ice.
So what is the polar vortex? How does it affect mid-latitude weather? And what role – if any – is climate change playing?
‘Beast from the East’
Many of the news headlines this week have been dominated by two sides of the same story. On one hand, the “Beast from the East” has swept across Europe, bringing freezing conditions and blizzards, leaving transport systems at a standstill in many countries.
Selection of ‘Beast from the east’ headline coverage. Credit: Tom Prater, Carbon Brief
Temperatures across Germany tumbled to below -10C; homeless people in Brussels were detained overnight if they refused shelter; and roofs of dozens of houses collapsed under the weight of snow in Bosnia-Herzegovina. Snow even made a rare appearance in Rome.
There Will Be Consequences
Posted on 6 March 2018 by Riduna
It snows in Antarctica and has done so every day for millions of years. As it snows, air is trapped among the snowflakes. As snowflakes accumulate their combined weight increases, compressing lower layers into ice. Air trapped among the snowflakes become air bubbles in the ice and the deeper the ice, the older the air bubbles.
Drilling down through the ice has recovered ice cores containing air bubbles over 800,000 years old. Placing ice from these cores in a vacuum tube, then allowing it to melt releases ancient air. This is then analysed to find out what gases are present in the recovered air sample, an exercise which has been repeated again and again from air samples stretching back over millennia.
This air is analyzed, revealing the changing composition of Earth's atmosphere, particularly carbon dioxide (CO2) and methane (CH4) in this 800,000 year record (fig 1).
Fig 1. minimum and maximum volume of CO2 correspond to the coldest period of ice ages and thermal maxima during interglacial periods.
The record shows that during the coldest periods – ice ages – the average concentration of CO2 in the atmosphere has been found to be 175 ppm. By contrast, during thermal maxima, concentration rises to around 285 ppm. By mid 2017, CO2 concentration had reached an unprecedented 406.5 ppm, or 40% above normal.
Stop blaming ‘both sides’ for America’s climate failures
Posted on 5 March 2018 by dana1981
Steven Pinker is a cognitive psychologist, linguist, and author of Bill Gates’ two favorite books. However, his latest – Enlightenment Now – has some serious shortcomings centering on Pinker’s misperceptions about climate change polarization. Pinker falls into the trap of ‘Both Siderism,’ acknowledging the Republican Party’s science denial, but also wrongly blaming liberals for the policy stalemate, telling Ezra Klein:
there is implacable opposition to nuclear energy in much of the environmental movement ... There are organizations like Greenpeace and NRDC who are just dead set opposed to nuclear. There are also people on the left like Naomi Klein who are dead set against carbon pricing because it doesn’t punish the polluters enough ... the people that you identify who believe in a) carbon pricing and b) expansion of nuclear power, I suspect they’re a tiny minority of the people concerned with climate … What we need are polling data on how many people really would support carbon pricing and an expansion of nuclear and other low carbon energy sources.
Here Pinker has created a strange straw man that bears no resemblance to the real population of American liberals and environmentalists. In fact, the polling data he wonders about already exists.
For example, a 2016 survey by Yale and George Mason universities found that 73% of Democrats support a carbon tax or a combination of tax and regulations (a further 17% favored carbon pollution regulations only). In fact, most consider putting a price on carbon pollution the single most crucial step in tackling global warming. Even Naomi Klein has said, “I don’t think a carbon tax is a silver bullet, but I think a progressively designed carbon tax is part of a slate of policies that we need.”
While it’s true that a majority of liberals oppose building more nuclear power plants, 38% support the idea. Some environmental groups like Greenpeace do oppose nuclear power, but Pinker’s other example, NRDC merely points out that new nuclear plants are currently uneconomical, and even suggests, “The federal government should continue to fund research into nuclear energy.” There are strong economic reasons to oppose building new nuclear power as an inefficient use of resources when renewables today are cheaper and can be deployed more quickly. That being said, were nuclear power funding included in comprehensive legislation to tackle climate change, most liberals and environmentalists would accept that deal in a heartbeat.
2018 SkS Weekly Climate Change & Global Warming Digest #9
Posted on 4 March 2018 by John Hartz
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The North Pole just had an extreme heat wave for the 3rd winter in a row
As snow falls in Rome, the Arctic is getting alarmingly hot in the middle of winter.
The Arctic was 5.1 degrees Celsius warmer than normal on February 27, following several days of unusually hot weather. Climate Reanalyzer
It’s been downright toasty at the North Pole, at least by Arctic standards.
The northernmost weather station in the world, Cape Morris Jesup in Greenland, saw temperatures stay above freezing for almost 24 hours straight last week, and then climb to 43 degrees Fahrenheit (6.1 degrees Celsius) on Saturday (Feb 24) before dropping again.
But that Saturday (Feb 24) temperature was a whopping 45 degrees Fahrenheit above what’s normal this time of year:
The North Pole just had an extreme heat wave for the 3rd winter in a row by Umair Urfan, Energy & Environment, Vox, Feb 28, 2018
2018 SkS Weekly Climate Change & Global Warming News Roundup #9
Posted on 3 March 2018 by John Hartz
A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week.
We’ve radically underestimated how vulnerable Americans are to flooding
New research claims that official estimates lowballed the risk by, uh, about a factor of three.
A giant nor’easter — incongruously named Winter Storm Riley, like some Brooklyn kid’s play date — is expected slam into New England coast today, bringing snow, rain, high tides, and damaging winds.
The Boston Globe reports that the National Weather Service has “high confidence” that the eastern coast of Massachusetts is going to experience “moderate to major flooding.” It has “moderate confidence” that heavy rains of two to three inches could cause urban and street flooding throughout southeastern Massachusetts, including Boston.
[HAZARDS] Updated. Coastal flood warning E MA, advisory S MA & RI; hurricane / storm force wind warnings for the waters; high wind warning & advisory across the interior; flood watch for E MA, RI & CT; winter storm warning for the high terrain ... Mainly Friday through Saturday
So it is somewhat ironic (if that’s the word) that this week also features the publication of a new paper in Environmental Research Letters showing that Americans are at far greater risk from flooding than official estimates reveal — as in, three times the risk.
We’ve radically underestimated how vulnerable Americans are to flooding by David Roberts, Energy & Environment, Vox, Mar 2, 2018
New research, February 19-25, 2018
Posted on 2 March 2018 by Ari Jokimäki
A selection of new climate related research articles is shown below.
Climate change impacts
1. Warmer winters reduce the advance of tree spring phenology induced by warmer springs in the Alps
"Our results showed that for similar preseason (i.e. after dormancy break) temperatures, warmer winters significantly delayed budburst and flowering along the elevation gradient (+0.9 to +5.6 days °C−1) except for flowering of Corylus and budburst of Picea. For similar cold winter temperatures, warmer preseasons significantly advanced budburst and flowering along the elevation gradient (−5.3 to −8.4 days °C−1). On average, the effect of winter warming was 2.3 times lower than the effect of spring warming. We also showed that warmer winter temperature conditions have a significantly larger effect at lower elevations. As a consequence, the observed delaying effect of winter warming might be beneficial to trees by reducing the risk of exposure to late spring frost on a short term. This could further lead to partial dormancy break at lower elevations before the end of the 21st century, which, in turn, may alter bud development and flowering and so tree fitness."
2. Precipitation alters temperature effects on ecosystem respiration in Tibetan alpine meadows
3. Non-uniform time-lag effects of terrestrial vegetation responses to asymmetric warming
"NPP responds to asymmetric warming (AW) with near 12-month lags globally."
Actions today will decide Antarctic ice sheet loss and sea level rise
Posted on 1 March 2018 by dana1981
A new study published in Nature looks at how much global sea level will continue to rise even if we manage to meet the Paris climate target of staying below 2°C hotter than pre-industrial temperatures. The issue is that sea levels keep rising for several hundred years after we stabilize temperatures, largely due to the continued melting of ice sheets in Antarctica and Greenland from the heat already in the climate system.
The study considered two scenarios. In the first, human carbon pollution peaks somewhere between 2020 and 2035 and falls quickly thereafter, reaching zero between 2035 and 2055 and staying there. Global temperatures in the first scenario peak at and remain steady below 2°C. In the second scenario, we capture and sequester carbon to reach net negative emissions (more captured than emitted) between 2040 and 2060, resulting in falling global temperatures in the second half of the century.
The authors found that global average sea level will most likely rise by about 1.3 meters by 2300 in the first scenario, and by 1 meter in the second. However, there is large uncertainty due to how little we understand about the stability of the large ice sheets in Greenland and especially Antarctica. At the high end of possible ice sheet loss, we could see as much as 4.5 meters of sea level rise by 2300 in the first scenario, and close to 3 meters in the second scenario.
Carbon emissions (top frames), global temperatures (middle frames), and sea level rise (left frames) in the study’s two scenarios (left and right frames). Illustration: Mengel et al. (2018), Nature Communications
What role did climate change play in this winter’s US freezes, heat, and drought?
Posted on 28 February 2018 by dana1981
This is a re-post from the Citizens' Climate Lobby Blog by Dana Nuccitelli and Doug Sinton, CCL Science Policy Network Team
There is growing scientific evidence suggesting that human-caused global warming is causing rapid changes in the Arctic, which in turn is altering the atmosphere, causing wavy patterns to form more frequently in the jet stream. On the West Coast, this can cause persistent high-pressure systems to form in the Pacific, exacerbating droughts by blocking storm systems. It can also allow frigid Arctic air to spill into the USA, creating especially cold winter weather. In sum, these freezes, heat, and droughts are made more likely by rising global temperatures, and as they rise further, such extremes may well become more common.
Abnormal winter weather
This winter, the eastern USA was hit by frigid cold weather, although at the same time, the western states (and most of the rest of the world) were relatively toasty:
North American surface temperatures for Dec. 26, 2017 – Jan. 2, 2018, from NASA Earth Observatory
This prompted a presidential tweet suggesting, “Perhaps we could use a little bit of that good old Global Warming.” It’s a natural reaction, when in the midst of frigid weather, to wonder how such cold conditions can strike in a world that’s being heated by global warming. However, scientific research has suggested that, counterintuitively, climate change appears to be playing a role in making these cold winter weather events happen more often in some regions.
Scientists have detected an acceleration in sea level rise
Posted on 27 February 2018 by John Abraham
As humans emit heat-trapping gases like carbon dioxide, the planet warms, and over time consequences become more apparent. Some of the consequences we are familiar with – for instance, rising temperatures, melting ice, and rising sea levels. Scientists certainly want to know how much the Earth has changed, but we also want to know how fast the changes will be in the future to know what the next generations will experience.
One of the classic projections into the future is for sea level rise. It is expected that by the year 2100, the ocean levels will rise a few feet by the end of the century. This matters a lot because globally, 150 million people live within three feet of current ocean levels. We have built our modern infrastructure based on current ocean levels. What happens to peoples’ homes and infrastructure when the waters rise?
But projecting ocean levels into the future is not simple; we need good data that extends back decades to understand how fast the climate is changing. The classic way to measure ocean levels is by using tide gauges. These are placed just offshore, around the globe to get a sense of how the ocean levels are changing. The problem with tide gauges is they only measure water levels at their location, and their locations are always near shore.
In order to get a better sense of how oceans are changing everywhere, a complementary technology called satellite altimetry is used. Basically, the satellites shoot a radar beam from space to the ocean surface and watch for the reflection of the beam back to space. From this beam, the satellite can calculate the height of the water. Satellites can emit beams continuously as the satellite passes over open oceans, and can gather data far from shorelines. In doing so, they provide the equivalent of a global network of nearly half a million tide gauges, providing sea surface height information every 10 days for over 25 years.
Just recently, in the Proceedings of the National Academy of Sciences, a paper has been published that collects all the available satellite altimetry data and asks whether the sea level rise is accelerating. The authors of the paper are a well-respected team and include Dr. Steven Nerem from the Cooperative Institute for Research in Environmental Sciences (CIRES) and Dr. John Fasullo, from the National Center for Atmospheric Research.
Impact of climate change on health is ‘the major threat of 21st century’
Posted on 26 February 2018 by Guest Author
This is a re-post from Carbon Brief by Daisy Dunne
The health of millions of people across the world is already being significantly harmed by climate change, a major new report finds.
From driving up the number of people exposed to heatwaves to increasing the risk of infectious diseases, such as dengue fever, climate change has had far-reaching effects on many aspects of human health in last few decades, the authors say.
In fact, the effect of climate change on human health is now so severe that it should be considered “the major threat of the 21st century”, scientists said at a press briefing held in London.
The report is the first from the Lancet Countdown on Health and Climate Change, a project involving 24 academic institutions and intergovernmental organisations from across the world. The project plans to release a report tracking progress on climate change and global health every year.
2018 SkS Weekly Climate Change & Global Warming Digest #8
Posted on 25 February 2018 by John Hartz
Story of the Week... Editorial of the Week... Toon of the Week... Quote of the Week... SkS in the News... SkS Spotlights... Video of the Week... Coming Soon on SkS... Poster of the Week... Climate Feedback Reviews... SkS Week in Review... 97 Hours of Consensus...
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Dirty industry undermines push to curb global warming - ex-UN climate chief
"The United States is in a whopping collection of one country"
Industry's dependence on polluting fossil fuels is at odds with a "revolution" in transport and renewable energy, and could stop the world doing a crucial U-turn on rising emissions of climate-changing gases by 2020, a former U.N. climate chief warned.
Christiana Figueres, who oversaw work on the 2015 Paris Agreement to tackle global warming, now leads "Mission 2020", an international initiative that seeks to put greenhouse gas emissions on a downward path by 2020.
"We're definitely not on track with everything to do with heavy industry that continues to depend on intense, high-carbon electricity, and we're not on track with land use," said Figueres, former executive secretary of the U.N. Framework Convention on Climate Change.
"So what happens if we don't get there is we increase our risk and increase the exposure to extreme weather events," she told the Thomson Reuters Foundation in an interview.
Dirty industry undermines push to curb global warming - ex-UN climate chief by Sophie Hares, Thomson Reuters Foundation, Feb 23, 2018
2018 SkS Weekly Climate Change & Global Warming News Roundup #8
Posted on 24 February 2018 by John Hartz
A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week.
Seas Will Rise for 300 Years
And the longer it takes to reduce carbon emissions, the higher they will go
Credit: Erika Maldonado Flickr (CC BY 2.0)
Seas Will Rise for 300 Years by Chelsea Harvey, E&E News/Scientific American, Feb 21, 2018
New research, February 12-18, 2018
Posted on 23 February 2018 by Ari Jokimäki
A selection of new climate related research articles is shown below.
The Figure is from paper #24.
1. Climate Change Attribution: When Is It Appropriate to Accept New Methods?
2. Does the projected pathway to global warming targets matter?
3. Isolating the meteorological impact of 21st century GHG warming on the removal and atmospheric loading of anthropogenic fine particulate matter pollution at global scale
4. Assessment of climate change in Algeria from 1951 to 2098 using the Köppen–Geiger climate classification scheme
Standing Rock is everywhere: one year later
Posted on 22 February 2018 by Guest Author
Chief Arvol Looking Horse is the 19th Keeper of the Sacred Bundle and Spiritual Leader of the Lakota, Dakota, Nakota People.
One year after the closing of the camp at the Standing Rock Reservation, Standing Rock is everywhere. Our collective water has been assaulted for many generations to the possible point of no return.
Our Elders foretold of a Black Snake and how the Water of Life — “Mni Woc’oni,” which is our first medicine — would be affected if we did not stop this oncoming disaster. Mni Woc’oni is part of our creation story, and the same story that exists in many creation stories around Mother Earth.
When we say “Mni Woc’oni” — Water of Life — people all over the world are now beginning to understand that it is a living spirit: it can heal when you pray with it and die if you do not respect it. We wanted the world to know there have been warnings in our prophecies and, as we see it, those warnings are now taking place. It was said water would be like gold. It was said that our spirit of water would begin to leave us.
We are at the crossroads.
First sunrise begins to creep onto Oceti Sakowin Camp, October 19th, 2016. Photograph: Ryan Vizzions
It's a given of climate change that greenhouse gases emitted today will shape the world for future generations. But new research underscores just how long those effects will last.
A striking new study published yesterday in the journal Nature Communications suggests that sea-level rise—one of the biggest consequences of global warming—will still be happening 300 years from now, even if humans stop emitting greenhouse gases before the end of the current century.
What's more, the longer it takes to start reducing global emissions, the higher those future sea levels will be. The study suggests that for every additional five years it takes for emissions to peak and start falling—for instance, if emissions were to reach their maximum levels in the year 2030, as opposed to 2025—sea levels will rise an additional 8 inches by the year 2300.
What I Learned about Climate Change: The Science is not Settled
- David Siegel
THIS ESSAY has had over 180,000 views. Please link to ClimateCurious.com. Welcome new readers from my Interview with Barack Obama. Enjoy!
What is your position on the climate-change debate? What would it take to change your mind?
If the answer is It would take a ton of evidence to change my mind, because my understanding is that the science is settled, and we need to get going on this important issue, that’s what I thought, too. This is my story.
More than thirty years ago, I became vegan because I believed it was healthier (it’s not), and I’ve stayed vegan because I believe it’s better for the environment (it is). I haven’t owned a car in ten years. I love animals; I’ll gladly fly halfway around the world to take photos of them in their natural habitats. I’m a Democrat: I think governments play a key role in helping preserve our environment for the future in the most cost-effective way possible. Over the years, I built a set of assumptions: that Al Gore was right about global warming, that he was the David going up against the industrial Goliath. In 1993, I even wrote a book about it.
Recently, a friend challenged those assumptions. At first, I was annoyed, because I thought the science really was settled. As I started to look at the data and read about climate science, I was surprised, then shocked. As I learned more, I changed my mind. I now think there probably is no climate crisis and that the focus on CO2 takes funding and attention from critical environmental problems. I’ll start by making ten short statements that should challenge your assumptions and then back them up with an essay.
1Weather is not climate. There are no studies showing a conclusive link between global warming and increased frequency or intensity of storms, droughts, floods, cold or heat waves. The increase in storms is simply a result of improved measurement methods. There has been no real increase.
2Natural variation in weather and climate is tremendous. Most of what people call “global warming” is natural, not man-made. The earth is warming, but not quickly, not much, and not lately.
3There is tremendous uncertainty as to how the climate really works. Climate models are not yet skillful; predictions are unresolved.
4New research shows fluctuations in energy from the sun correlate very strongly with changes in earth’s temperature, better than CO2 levels.
5CO2 has very little to do with it. All the decarbonization we can do isn’t going to change the climate much.
6There is no such thing as “carbon pollution.” Carbon dioxide is coming out of your nose right now; it is not a poisonous gas. CO2 concentrations in previous eras have been many times higher than they are today.
7Sea level will probably continue to rise — not quickly, and not much. Researchers have found no link between CO2 and sea level.
8The Arctic experiences natural variation as well, with some years warmer earlier than others. Polar bear numbers are up, not down. They have more to do with hunting permits than CO2*.
9No one has demonstrated any unnatural damage to reef or marine systems. Additional man-made CO2 will not likely harm oceans, reef systems, or marine life. Fish are mostly threatened by people, who eat them. Reefs are more threatened by sunscreen than by CO2.
10The Intergovernmental Panel on Climate Change and others are pursuing a political agenda and a PR campaign, not scientific inquiry. There’s a tremendous amount of trickery going on under the surface*.
Could this possibly be right? Is it heresy, or critical thinking — or both? If I’ve upset or confused you, let me guide you through my journey.
I won’t present all the science. Instead, my goal is to give you a platform for investigating the other side of the debate, so you can form your own opinion. I have noted important and quick reads with an asterisk* — if you have time for further study, start with those videos and documents. Here are the sections:
- Critical Thinking
- Four Hard Questions
- The Climate Consensus
- Manufacturing Consensus
- Who Can We Believe?
- What Should We Do?
- What Do You Think?
This nine-thousand-word essay represents over 400 hours of research boiled down into a half-hour reading experience, with links to 250+ carefully chosen documents and videos. I’m building the argument from the bottom up, so take your time and see if it makes sense. Along the way, I’ll list five “smoking guns” that I think make the argument for decarbonization unsupportable. Before we dive in, I want to talk about …
M y journey into critical thinking has taught me to hold strong opinions loosely. I’ve been more wrong in my life than I thought was possible. Now I try to put my reactions aside and look at all the evidence before coming to a conclusion.
Policy always involves politics. Governments often make policy decisions by starting with a social objective and then bring in the “facts” to justify the goal (think of the Vietnam war, the Iraq war, Prohibition, the War on Drugs, and others). We shouldn’t be surprised to find social agendas driving at least some of the “science” of global warming.
In addition, studies show that political beliefs cloud our ability to process information. Strong political beliefs can cause us to look at one side of an issue and ignore the evidence. We should try to avoid shortcuts and look directly at the data.
Forecasts are mental constructs; they are not properties of the physical world. Forecasts are tools, not truth. In most cases, the size of the error bars (uncertainty) around the number is more important than the number itself.
Consensus is not an argument for any scientific principle. Many important scientists toiled alone to make discoveries that were less than popular. One key paper can be worth more than thousands of papers reinforcing a myth. The claim that 97 percent of scientists believe in man-made global warming is one such myth. Almost all scientists expect a small man-made contribution to warming, so the claim is misleading.
Metastudies are important. One key paper can be a breakthrough, but there are very few of those. A better source of information is properly done metastudies (reviews of all the literature on a topic) conducted by qualified statisticians. They help find the signal in the noise.
There is a big climate conference coming up in Paris in December, 2015. Diplomats will debate the merits of an agreement that promises to steer hundreds of billions of dollars toward reducing carbon emissions, mostly in large developing countries. Is it based on sound science? Let’s ask four hard questions and see what we can learn …
- What are the natural drivers of temperature and its variability?
- What does the projected natural increase in temperature mean for the environment and people?
- What does the increase in greenhouse gases from human activity mean for oceans, environment, animals, habitats, and humanity?
- Is Decarbonation the Right Solution?
Let’s look with fresh eyes and see what we can learn.
1. What are the natural drivers of temperature and its variability?
Incoming solar radiation is the primary driver of temperature. A second factor is the atmosphere, which traps heat and reflects some of it back to earth. Other factors play smaller roles. I’ll start with the familiar greenhouse-gas model and then present a more accurate picture based on solar activity.
The Greenhouse Effect
In this section, I focus on CO2 because it’s regarded as the main greenhouse gas after water vapor. Looking at the 750-million-year graph below, we see some extreme cold periods, then warm epochs punctuated by ice ages, all while CO2 (yellow) was far above what it is today. There is almost no correlation between temperature and carbon dioxide until about ten million years ago.
Starting around a million years ago, the curves start to sync up, and we see a pretty definitive supercycle of about 100,000 years for both:
Think about that: CO2 had no correlation with temperature for more than 2 billion years, and now it’s causing temperature to rise? Something’s going on, but what? Let’s zoom in:
Notice that temperature generally changes first, and CO2 changes some 800+ years later. Blue line to the left, red line to the right. This is called the temperature lag — an inconvenient truth for CO2-warming enthusiasts; it’s well known but not well understood. It could easily be a complex relationship, but CO2 changes do not initially cause historical temperature changes.
On a shorter time scale, we start to get some perspective:
At this scale of 11,000 years, it doesn’t seem like CO2 is “driving” temperature. We are in the middle of an upswing coming out of the Little Ice Age, but there is also an overall cooling trend.
Before the twentieth century, there was plenty of temperature variability, and it continues today. If you have heard about the hockey-stick controversy, it’s about whether this graph created by Michael Mann, which Al Gore likes to stand in front of on a scissor lift, represents reality:
It doesn’t. Despite what you read on Wikipedia, this graph was manufactured by carefully cherrypicking the data from tree rings. Looking at tree rings is about the least accurate way to measure ancient temperatures. Better methods involve looking at drilled ice and sediment cores. Using those methods, we see a pronounced period warmer than today from 1000 to 1300 AD, called the Medieval Warm Period, and then the Little Ice Age about 400 years ago (same time period as above):
This single issue invalidates many of Al Gore’s claims* and undermines the IPCC’s predictions of man-made CO2 catastrophe. (You’ll find a list of relevant studies at CO2Science.org*.)
Smoking gun #1: The Hockey Stick is Wrong; The Medieval warming period was real and worldwide.
Once I understood that the IPCC was playing games, I realized I had a lot of work to do to uncover the rest of the story. It starts with data manipulation.
Where Does the Data Come From?
For the last 80 years, we have far more accurate ways of recording temperature, so the far right hand side of the graph above should come from direct measurements. Weather stations that gather this data differ in quality and consistency, especially over decades as the areas around them develop. A large-scale reassessment of all US weather stations from 1979 to 2008 carefully divided the stations into five classes, from best quality (I) to worst (V). For this period of time, they calculated the per-decade average temperature increases, and found:
- Class I and II only (most accurate): 0.155 C
- Class III, IV, and V sites only: 0.248 C
- NOAA 2015 “adjusted” calculation: 0.309 C
What does that tell you? NOAA is “adjusting” their data to increase warming figures far out of the realm of possibility. The IPCC relies mostly on NOAA data and other similarly adjusted data, which conveniently provides an instant doubling of temperature increase, making all the graphs much steeper after 1980.
The science is extremely complex and uncertain. If you have blind faith in the wrong numbers, you’re going to jump to the wrong conclusions.Anthony Watts has carefully reviewed NOAA’s data and found unscientific manipulation. Watch this 15-minute video* and decide for yourself*:
NOAA continues to “adjust” their data, manufacturing graphs that support the cause.
Smoking gun #2: Government agencies have rigged climate data to support man-made global warming.
Note: It’s easy to find nonscientific articles and videos that “prove” the hockey stick has been validated by updated research and that the sun’s energy doesn’t fluctuate. However, one central tenet of journalism is that you can’t fact-check a source by asking the source, and that’s exactly what most journalists are doing. To fact-check the IPCC, look at the peer-reviewed literature written by scientists who are not in the IPCC.
That’s the greenhouse-gas theory. Now on to more recent research.
Many solar variables contribute to the variance we see in temperature: distance, orbit cycles, axis tilt, magnetic fields, sunspots, solar wind, cosmic rays, the passage of earth through our galaxy, etc. Even though the total energy coming from the Sun is nearly constant, a) those tiny fluctuations can make a difference, and b) there are many other factors that can and do change. In particular, magnetic field changes can have significant influence on the shape of the jet stream, and that can influence cloud formation.
Willie Soon, a solar physicist, showed that the tiny variations in incoming solar radiation can have a more direct effect on temperature than CO2 does, but it takes very sensitive measurements and careful analysis to see the signal. Willie and his team first did many months of inspecting data from weather stations in the Northern Hemisphere*, throwing out spurious and made-up measurements, to put an accurate temperature picture together (blue line):
Then they plotted total solar irradiation (TSI) and found a very good first-order correlation, much better than with CO2. The graph above is probably the most accurate picture we have for that time period. Below is a similar exercise for the United States:
Note that this graph accurately shows the most recent cooling trend since 1998 without any hand waving.
Smoking gun #3: Solar fluctuations correlate better with observed temperature fluctuations.
Not only do fluctuations in solar energy drive changes in climate, the oceans react to increases in solar energy by generating clouds that help regulate temperature. Since 2013, much research has been aimed at constructing a more accurate picture of past temperature/solar radiation correlation and developing a realistic solar-driven climate prediction model*, taking the greenhouse effect into account.
Sunspots fluctuate in roughly 11-year cycles. It’s complicated, but in general these cycles show a moderate amount of correlation with temperature. The period of no sunspot activity 400 years ago corresponds to the Little Ice Age, when winters were significantly colder than they are today.
The current cycle peaked in 2014. Solar experts speculate that the next cycle, which starts in 2020, will have fewer sunspots. If that turns out to be true, temperatures could be heading down, rather than up. Reactions to this cooling prediction range from “unlikely,” to “plausible,” to “probable.” Whatever mechanism causes sunspots could be part of the picture, but there are several different solar cycles, different research approaches, and competing theories. They are converging, but it’s a complex work in progress. A single predictive model is still years or decades away.
Hottest Year on Record?
When you hear claims of this year being “the hottest year on record,” you should understand that 1922, 1998, and 2010 were also extremely hot, and the El Niños were extreme then as well. That’s not a trend; that’s a local peak. Look at the last 18 years from satellite data:
How many peaks do you see that are higher than this year’s? Now look at the scale — it’s one degree Celsius from top to bottom. To give you a sense of how up and down this really is, I traced the graph above and put it in perspective of the 20 degrees C (36 degrees F) we might experience in a single day:
Same data, different perspective. Can you see the hottest year on record now? In any given year, several weather stations will record dramatic “all time highs” with no effect on global temperatures.
No one knows what will really happen. We can’t see the future. We know CO2 is increasing relentlessly, yet temperatures are not. If you believe in the IPCC models, then you need worldwide temperatures to start going up, and soon. A few more hurricanes wouldn’t hurt, either. If you agree that solar activity primarily drives climate changes, then you will probably agree with the current scientific consensus outside the IPCC and with the conclusions of a recent metastudy on temperature forecasts: one degree C of warming this century, plus or minus one degree. That’s the 90%-confidence prediction at this point, but there’s always a chance that they are wrong, or that things will change unexpectedly. We’ll know a lot more in another twenty years or so.
2. What does the projected natural increase in temperature mean for the environment and people?
Sea level won’t likely rise in response to increased CO2. For starters, sea level rises and falls more than people think. Global mean sea level rose about 15 cm (6 inches) in the twentieth century. The IPCC models predicted higher levels by now, but researchers have found no link between CO2 and sea level. Sea level rises linearly; the rate of rise is not increasing. Any rise so far is very much in line with natural factors, not man-made. Estimates range from 5-20 cm (2–8 inches) of sea level rise (naturally) by the end of this century.
Reef systems and marine life will not likely be harmed by additional CO2. Researchers use tank experiments and computer models to predict doom and gloom (this approach is full of errors). Despite what you read in the press, no one has yet seen any verifiable signs of manmade CO2 effects, or even pollution. Coral bleaching is a natural phenomenon caused by temperature changes, especially in El Niño and La Niña years — it’s been going on forever.Live reef experiments have shown that coral polyps adapt well to changes in pH, but sunscreen is toxic. Furthermore, a recent metastudy found no evidence of harm due to “ocean acidification” and no likely harm in the future. If you care about ocean life, stop eating it! Stop developers from replacing estuaries, wetlands, and mangrove swamps with condos. And please stop eating shrimp immediately.
Freak storms are a far bigger threat. Again, storms are not caused by global warming. Over the next hundred years, as our population reaches nine billion or so, we should expect extreme events to have catastrophic consequences around the globe as a result of massive-scale urbanization and natural variance . Damage figures will rise significantly as we build larger cities on the coasts and expensive buildings with sea views. Don’t be fooled by graphs showing rising damage figures — they are guaranteed! The science is settled on this — even the IPCC admits that none of it is driven by CO2.
Let’s talk about polar bears. The health and numbers of the Arctic’s 19 polar bear populations are in very good shape, better than in decades*. Mitch Taylor, who has studied polar bears for over 30 years, says populations are increasing and very resilient. Each year at least 600 polar bears are shot, killed, and eaten by hunters — did your favorite news source tell you that? Arctic sea ice grows and shrinks by an area almost the size of the continental United States every six months. As the planet gently warms, the overall trend for slightly less ice each year continues; all the animals who live there have been dealing with this kind of fluctuation for millions of years. International fishing and seal hunting quotas have more to do with polar bear numbers than temperature does.
Furthermore, Greenland is not melting into the sea because of global warming. Greenland’s temperature fluctuates all by itself and always has.
Far from the land of polar bears, we hear tales of extreme temperatures melting Antarctic ice sheets the size of Wyoming. Despite the fact that glaciers fall into the ocean dramatically each year, Antarctica’s ice is actually increasing (reason: it snows in Antarctica, but snowfall doesn’t make good news footage). Imagine a time-lapse movie of Antarctica over the past million years or more: we see huge amounts of ice accumulating, moving, dropping into the sea, over and over. We shouldn’t be surprised to watch the Larsen B ice shelf fall into the sea — it should take extraordinary evidence to convince us that this is not natural. To think Antarctica should stay the same as it was when we were children is to commit the error of base-rate neglect. Remember this: the Arctic is losing a bit of ice each year, and the Antarctic is gaining a bit.Not much. And not quickly.
If the worst isn’t going to happen, a small rise in temperature should benefit society. CO2 helps plants grow. Excessive cold kills far more people than excessive heat does.
3. What does the increase in greenhouse gases mean for oceans, environment, animals, habitats, and humanity?
This is the domain of climate models. I could write twenty pages, but I’ll summarize my research:
- According to Bob Tisdale, a researcher I respect after reading his book Climate Models Fail, the IPCC models simply aren’t skillful. They failed to predict the past twenty years, they don’t realistically model the cloud response, and there is simply too much uncertainty about the inputs to get decent outputs.
- NASA GISS, in realizing that global temperatures refuse to conform to their models, has said that the increase in heat is trapped in the oceans. This bit of model trickery also does not stand up to careful analysis.
- The IPCC models are falsifiable — if temperature doesn’t go up over the next ten years or so, we will have to agree that the IPCC models are, and always were, dead wrong. It is not looking good.
- According to J Scott Armstrong, all climate models so far don’t meet the minimum criteria for a skillful forecast. He has testified before congress on climate forecasts, polar-bear counts, and other misconceptions. Here is his 15-minute talk:
Armstrong and other modeling experts say the simple “no change” prediction is often far superior to a complex one with many independent variables. In that case, we can predict about another one-degree C rise for this century, and another 3–7 centimeters of gradual sea-level rise.
Smoking Gun #4: Rigged Inputs and Wrong Assumptions About Feedback Lead to Computer Model Failure.
Correlation is not Causation
Killer storms. Bee colony collapse. Mosquito-borne diseases. Ticks heading south for the winter. Heat-related deaths. Arctic lobster populations. Algae blooms. Global temperatures. These things may or may not be increasing, but let’s assume they are. Atmospheric carbon dioxide is also increasing. So are the number of toilets made every year and the number of vinyl records sold. When a particular scientist issues a press release describing the future collapse of ecosystems, I recommend asking “What evidence do you have?” When they say something we can see today is due to “anthropogenic global warming,” they are saying that the extra 120 parts per million of CO2 in the atmosphere — about 30% of the total — are causing the phenomenon right now, as opposed to all other possible natural explanations, including variance. I recommend asking, “How can you be sure?” Just because we haven’t seen something in the past century doesn’t mean it wasn’t going to occur anyway.
This is the scientific method — ask hard questions, develop hypotheses, and try to disprove them. Not only do we need better models, we need to be empirical, not hysterical. We need to look at the data and separate the signal from the noise. The majority of single papers showing research results are simply wrong. To get a better picture of scientific findings, one of the best tools is the metastudy.
Smoking Gun #5: All metastudies so far disagree with the IPCC projections.
We only have two so far, but they are significant: one on temperature, and one on ocean acidification. Anyone who claims otherwise is going to have to explain why his/her claim invalidates the metastudies. That’s a lot to ask, but this is the level of proof science demands.
4. Is decarbonization the right solution?
Okay, but even if there’s a lot of uncertainty, what about the small possibility that something really bad could happen? Shouldn’t we put money and resources into doing something, just as an insurance policy?
We could, but we have to balance that against buying other things with the same money and effort*. Right now, some ecosystems are fragile and threatened by humanity, while many others are already repairing themselves*. The focus on CO2 may be misplaced. It’s not the CO2 that causes choking smog in Los Angeles, it’s the rest of the mix that comes from the power plant and out of exhaust pipes. It’s the fact that China needs to build a new city the size of Phoenix every month for the next 15 years. More people are eating a western diet, contributing to deforestation and wasting resources. Overfishing is a crisis in progress. This and much more is actually happening today, not in a computer model.
The Bush administration held up the Kyoto agreement, yet they spent trillions on a war based on no verifiable evidence to prevent a future that was never going to happen. Should we really do the exact opposite?
Enter Bjorn Lomborg, the “skeptical environmentalist,” who has spent his mediagenic career trying to prioritize our efforts to save the earth and humans along with it. According to his calculations, the EU’s goal of spending $250 billion per year until the end of the century will result in — and this is not a typo — 0.1 degree lower temperatures.
Lomborg’s book, Cool It, and movie of the same name, are excellent (though for some reason he believes the IPCC projections). He says we should switch to renewable sources of energy, but for the right reasons at the right price.
That’s my attempt to answer the four questions. For a good summary, see Nir Shaviv’s paper or Bob Tisdale’s excellent ebook. In the next three sections, I’ll quickly list people not to listen to and why, then I’ll list people I think we can trust.
This section is a guide to the IPCC and people sounding the alarm of impending climate doom.
The Intergovernmental Panel on Climate Change
The “mainstream climatologist” view is generally embodied by the IPCC. In 2007, the IPCC shared the Nobel Prize with Al Gore. Once I started to learn about the IPCC and the people who have left it and why, I started to question their motivations. The big shift came when I read a book called The Delinquent Teenager Who Was Mistaken for the World’s Top Climate Expert by Donna LaFramboise, detailing the methods and motivations of the IPCC. I highly recommend reading Laframboise’s book*; here are a few highlights:
- The IPCC operates in secrecy, leaves out critical pieces of data, relies too heavily on unproven measuring schemes, and tends to make unsupported sensationalist claims that support a politically-motivated, pre-determined agenda.
- Chris Landsea, a hurricane expert, resigned from the IPCC after a lead author for the IPCC and its chairman claimed that there would be more intense and more frequent storms as a result of man-made greenhouse gases. In his resignation letter, he wrote “I personally cannot in good faith continue to contribute to a process that I view as both being motivated by pre-conceived agendas and being scientifically unsound.”