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Archive for the ‘Global Warming’ Category

Thermodynamics Says There Is No “Hiatus “in Global Warming

Tue ,14/07/2015

During the 2008 Presidential Election,  John McCain proposed a pragmatic national energy policy based upon good stewardship, good science, and reasonableness. George Will attacked his proposal, claiming that “global temperatures have not risen in a decade”. He claimed the hottest year on record was 1998 and no year since has been hotter. His argument was simple, easily understood, and very wrong. While 1998 was an unusually hot year, NASA’s data shows that 2005 was warmer.

  • George Will’s claim resonated with those who wish to deny that the Earth is warming, so they extended the statement to “the Earth hasn’t warmed in 12 years”, 15 years, and finally 17 years – so far. Apparently truthfulness is not a criteria, as 2005, 2010, 2014, were warmer than 1998. Now they claim the International Panel on Climate Change (IPCC) has confirmed their deception. That’s not right, either.
  • The IPCC’s Fifth Assessment Report  concluded that the global surface temperature “has shown a much smaller increasing linear trend over the past 15 years [1998-2012] than over the past 30 to 60 years.” The apparent slowdown was termed a “hiatus” and cheered by the Skeptics, although a “smaller increasing linear trend” is not a hiatus. The apparent slowdown intrigued the climate scientists, who immediately set about trying to discover where the energy went.
  • Scientist knew the energy had to go somewhere  because of the First Law of Thermodynamics, which says that energy is conserved. The amount of carbon dioxide in the atmosphere was  still rising and, because of the greenhouse effect, the Earth was still absorbing more energy that it emitted. According to the conservation of energy, that extra energy has to go somewhere in the environment, and whether it warms the air, the land,  the oceans, melts ice, or evaporates water – the Earth was storing the energy somewhere. Claiming that “global warming has paused”, is badly misleading as the amount of energy in the Earth’s systems was still increasing. To claim a pause is to claim that the Law of Conservation of Energy is invalid. And, that is an extraordinary claim, requiring extraordinary proof. No Skeptic was up to that task.
  • What followed was a flurry of research by climate scientists,  trying to figure out where the energy had gone. It turned out that it really hadn’t gone  anywhere, because the missing heat has been there all along. It was an artifact from how the ocean temperatures were measured.
  • According to a recent NBC news report,”Global warming has not stopped or even slowed in the past 18 years, according to a new federal study that rebuts doubters who’ve claimed that that heating trends have paused. Scientists at the National Oceanic and Atmospheric Administration readjusted thousands of weather data points to account for different measuring techniques through the decades.”
  • Tom Karl, director of the National Centers for Environmental Information,  is the lead author of the  study published in the journal Science. He explained the discrepancy came from a change in how ocean temperatures were measured. “Global ocean temperatures are estimated both by thousands of commercial ships, which record the temperature of the water entering their engines and by thousands of buoys. The buoys tend to get cooler temperature readings than the ships, likely because ships’ engines warm the water. Meanwhile, in recent years, buoys have become increasingly common.”  The result, Karl says, is that the oceans did not appearing to be warming as much because more buoys are now being used instead of ships. So Karl’s team adjusted the buoy data to make them line up with the ship data. The corrected data,  in the graph below, shows that since 1998, the rate of warming is about the same as it has been since 1950: about two-tenths of a degree Fahrenheit per decade.



The Skeptics, of course, were not happy that the missing heat had been discovered and their ” hiatus” was exposed as a myth. So, they have now gone back to their familiar theme, that “scientists adjust the data to get what they want.” Saying that is certainly easier than disproving The First Law of Thermodynamics.

(C) 2015 – J.C. Moore

Bits and Pieces: Two Misguided Attacks on Wind Turbines and Electric Cars

Sun ,25/05/2014

There were two op-ed pieces in the May 25, 2014 Tulsa World which were misguided attacks on renewable energy and electric cars.

The first was titled “The Killing Fields”, with the subheading “Perverse federal energy incentive is a threat to birds, bats.” The article was written by Dr. George Fenwick who is the president of the American Bird Conservancy. The article was illustrated by an Associated Press photo which shows cattle standing in front of a windfarm in a drought prone area of Texas. It well illustrated flaws in Dr. Fenwick’s reasoning, he is more concerned about the wind turbines than about a much greater threat to bird populations.

While Dr. Fenwick had some good points in the article about the value of birds and our need to conserve them, the sensationalized article missed the greatest threat to birds. He complained about the federal production tax credit which encourages the development of wind energy, about allowing exception to the Endangered Species Act, and about siting of wind farms in sensitive areas. Wind developers are already avoiding sensitive areas and they have changed the design of wind turbines so they would be less of a threat to birds. He should have been more concerned about the bigger threats to bird populations, which are severe weather and the destruction of habitat, both made worse by global warming. Delaying the construction of wind turbines will certainly lead to more carbon emissions, making global warming more of a problem

Research shows that wind turbines are not among the top 10 human causes of bird mortality – and windfarms are likely saving HPIM2053amany more birds than they are killing. A comprehensive study of bird mortality in Canada found most human-related bird deaths (about 99%) are caused by feral and domestic cats, collisions with buildings and vehicles, and electricity transmission and distribution lines.  A related peer reviewed Canadian study of bird mortality found that less than 0.2% of the population of any bird species is currently affected by mortality or displacement by wind turbine development. They concluded that even though the number of windmills are projected to grow ten times over the next two decades, “population level impacts on bird populations are unlikely, provided that highly sensitive or rare habitats, as well as concentration areas for species at risk, are avoided.”

The fifth IPCC report says that the most important thing we can do to mitigate global warming is to switch to renewable energy as quickly as possible. If Dr. Fenwick’s sensationalized articles about “The Killing Fields” keeps us from developing renewable energy as quickly as possible, then he is working against the birds, and his own, best interest.

The second article, “Driving greener cars won’t save the Earth” by Megan McArdle essentially says efforts are futile to reduce our carbon emissions. She belittles her friend for buying an electric car and goes on that Americans are likely to do nothing significant to reduce our carbon emissions. She well documents all the ways that we waste energy and claims we are unlikely to change. She also points out that getting other countries, particularly China, to to reduce their carbon emissions is also futile. She concluded that if we want to get serious about reducing our carbon emissions then we need to find cheap renewable resources to replace our energy needs, to find a way to take greenhouse gases out of the air, or to keep the planet from warming because of those gasses that we have already put their .

Her last two suggestions show she does not have a good grasp of the scientific issues, but she is certainly right that we need cheap renewable resources. We have already found those in wind and solar, but they are not yet cheaper than fossil fuels because fossil fuels do not pay their external costs. The external costs for fossil fuels do not include health and environmental damage from particulates, nitrogen oxides, sulfur oxides, chromium, mercury, arsenic, and carbon emissions. An EU funded research study, Externalities of Energys ,  found that including externalities would increase the cost of producing electricity from fossil fuels by a factor of 30% for natural gas to about 90% for coal –  if costs to the environment and to human health were included. If we include those  costs, then sustainable energy sources have a big cost advantage. If we wish to be serious, then we need to remove subsidies to fossil fuels, require fossil fuels to pay their external costs, and to  subsidize renewable energy sources at the same level for several decades.

This falls into a long list of defeatist articles, such as that by Robert Bryce, which says that we are not going to be able to do anything about global warming, so why try. Yes, driving greener cars alone won’t save the Earth, but conserving energy, developing renewable energy sources, changing the energy sources we subsidize, and having fossil fuels pay their external costs, will certainly help more than writing articles discouraging us from trying.

  (c) 2014  J.C. Moore

Evidence Linking Global Warming and Extreme Weather

Thu ,08/05/2014

 “All weather events are affected by climate change because the environment in which they occur is warmer and moister than it used to be….  ”  – Trenberth


Kevin Trenberth, senior scientist at the National Center for Atmospheric Research, explains that asking for proof that global warming causes severe weather, is asking the wrong question. “All weather events are affected by climate change because the environment in which they occur is warmer and moister than it used to be. The main way climate change is perceived is through changes in extremes because those are outside the bounds of previous weather. The average anthropogenic climate change effect is not negligible, but nor is it large, although a small shift in the mean can lead to very large percentage changes in extremes. Anthropogenic global warming inherently has decadal time scales and can be readily masked by natural variability on short time scales.”

Scientists  have been very cautious about linking severe weather events to global warming, but the link is getting stronger each year. The Earth has warmed an average of 0.82 over the last century, which doesn’t sound like much, but it means that some places have warmed much more than in the past. Since the amount of moisture the air can hold depends on the temperature, the air can now hold about 6% more moisture. Before 2010, scientists would cautiously point out that higher temperatures lead to the likelihood of drought, and that more energy and moisture in the atmosphere was a recipe for severe weather. But how is it possible to establish that weather events were becoming more extreme?

There are many reports like the interim report by the Climate Council in Australia which found that, in the period between 1971 and 2008,  heatwaves in Australia were becoming more frequent, increasing in intensity and are lasting longer. The report said climate change was  having a key influence on a trend that has seen the number of hot days in Australia double and the duration and frequency of heatwaves increase. Reports like that were not good enough for the skeptics. By 2011 a good case was established that global warming was causing heat waves and droughts in the U.S., but the case was not strong enough to overcome the Skeptics objection, even when in 2012, a definite probability link  was established for  extreme temperatures and droughts. 

To understand whether a weather event is extreme, it must be compared to the norm. This can most easily be done for temperatures, as we have over a century of temperature records from almost all parts of the world.

Example of a Normal Distribution

Example of a Normal Distribution – Click to Enlarge

There is enough temperature data that normal distributions can be graphed, which allows us to quantify  the probability of a temperature event. In the example at the right, the maximum in the curve is the mean of the data. The probability of the occurrence of an event can be measured by the number of standard deviations, sigma(σ), a particular value is from the mean. The values within 2σ of the mean, blue, are considered to be in a mostly normal range. Those from 2 to 3σ, yellow, are considered to be exceptional events, and those beyond 3σ, red, are considered to be extreme. Those yearly events that fall in the yellow range are considered to be 100 year events while those that fall in the red are 1000 year event.

As an example, the normal distribution graph to the right is for the temperatures in Moscow since 1950.  The maximum in the curve is the average temperature, which is set to zero, and the temperature for other other year is described as a temperature anomaly, i.e., how far it is above or below the average value.Moscowjulytempanomaly2010 The curve approximates a normal distribution so the standard deviation of the temperature anomalies can be used to decide whether an event is extreme. The temperatures for 1972  and 2001 fall in the hundred year event range, while  that for 2010 would only be likely to occur only once in every hundred thousand years, unlikely, but still possible.

The Skeptics would still not be convinced, claiming that the link to global warming climate change causes severe weather was not proven, but proof is not necessary when probabilities for a large number of events are involved. For instance, you have only a 50% chance of calling a coin toss correctly, but you can likely guess the number of heads on 1000 flips with less than 1% error. Small differences in probabilities lead to big outcomes. The rules of blackjack give the house a 50.5% to 49.5% advantage, and though some players may win thousands on a lucky streak, considering all the bets placed, the house will make millions from that small difference in probability. And, probabilities are useful for predictions. A 0.270 hitter may get the game winning hit at his next bat while a 0.300 pinch hitter may strike out, but with the game on the line, the coach will likely pinch hit. If trying to predict the future, it is better to go with the probabilities. Though  it is not possible to prove that any one weather event is caused by global warming , scientists have observed a change in probabilities of severe weather events over long periods of time. With the thousands of weather events that occur on the Earth each year,  a small change in probability can cause an definite change in the number of severe weather events.  


An even more convincing argument can be made that global warming causes severe temperatures if the normal distribution is examined as a function of time. Research by James Hansen has established the link by showing that the normal distribution has changed since 1951. The curves show that beginning in about 1970, the mean begins to move to the right and the the curves flatten, showing that the probability of extreme temperatures increase greatly from 1950 to 2011.  His work shows that the probability of extreme temperatures is 10 times as great as for the 198o to 2010 years.

It should also be noted that the left side of the graph flattens, but that the probability of extremely cold temperatures is not zero. There is still a significant likelihood of cold temperatures -and a cold winter now and then does not disprove global warming.

The Skeptics are still claiming that is not proof enough, and that the data says nothing about droughts and wildfires.  There are still some Skeptics who argue that this does not mean  heat waves necessarily related to droughts or that the droughts are causing the increase in wildfires we have experienced, but their arguments seem to be improbable. It should be clear by now that no amount of evidence will convince Skeptics who wish to ignore probabilities.

(C) 2014  J.C. Moore



Global Warming and Pine Beetle Damage

Tue ,24/12/2013

Click to enlarge images.

On an environmental science field trip to the Cibola National Forest east of Albuquerque, the students noticed a large number of dead pine trees. The picture shows one that had been cut down, with the wood looking as if it had been shot full of holes with buckshot. The park ranger explained that the trees had been killed by the pine bark beetles which, because of climate change, have been extending their range to higher elevations in the park. The tree’s natural defense against the beetles is a secretion of pitch which forms a gooey protective barrier against beetles. The pine beetles do the most damage to mature trees that grow slower and produce less pitch, particularly when stressed by warmer temperatures and drought.

The quarter inch long beetles bore into the bark on mature trees and and create galleries in which they mate and lay eggs. The grubs feed in the inner bark and cambium layer, enlarging their tunnels as they grow. The “S” shaped tunnels can eventually girdle and kill the tree.  Mature larvae move to the outer bark and create a cell in which they pupate. When the new adults hatch, they chew through the bark, leaving small, clearly visible exit holes.  Most of the pine beetle damage is to the outer layer so the trees can still be used for lumber if harvested soon after the tree dies. Wood from beetle-affected trees retains its commercial value for 8 to 12 years after death, but the value drops rapidly during the first several months, as rapidly escaping moisture causes the wood to crack. The beetles also often introduce a blue stain fungus that can be lethal to the tree. Blue staining of the wood from the fungus is considered a defect, leading to a lower market price.

Normally, mountain pine beetles spend a winter as larvae in trees before emerging as adults the following summer. cycleIn the last two decades at the Colorado University Mountain Research Station, mean annual temperatures were 2.7 degrees Fahrenheit warmer than they were in the previous two decades. They found “The number of spring days above freezing temperatures increased by 15.1 in the last two decades, and the number of days that were warm enough for the beetles to grow increased by 44 percent since 1970.” This allows the beetles to produce an extra generation during most summers, leading to a rapid increase in the beetle population. The current bark beetle epidemic is the largest in history.

The bark beetles are a factor in wildfires as the large number of dead trees provide fuel for the fires. The needles stay on the trees for 2 or 3 years, contributing to canopy fires.  After the needles fall, the bare trees  contribute less to fires, but then they allow more sunlight through which melts the snow cover earlier and encourages the growth of underbrush, providing more fuel for wildfires. Compared with decades past, the traditional fire season now lasts two months longer in the West. The loss of trees also leads to earlier melting of snow which causes earlier runoff, contributes to heavier spring floods, and makes less water available later for streams and irrigation.

Because of global warming, the bark beetles have extended their range northward and to higher elevations, and their population is growing.  Andrew Nikiforuk, a Canadian journalist, has chronicled the plague of bark beetles that in the last quarter-century has killed more than 30 billion pine and spruce trees from Alaska to New Mexico. Though there are other factors, such as how the forests are managed, climate change is by far the greatest factor. Trees stressed by heat and drought can’t mount a strong defense against the beetles, whose numbers grow exponentially when they produce more than one generation per season. In one area in Canada, the bark beetle hatch produced a cloud of the insects large enough to show up on radar.

And it is not just in the West. The southern pine beetle is now spreading through New Jersey’s famous Pinelands. According to the article, “The tiny insect, firmly entrenched, has already killed tens of thousands of acres of pines, and it is marching northward. Scientists say it is a striking example of the way seemingly small climatic changes are disturbing the balance of nature. They see these changes as a warning of the costly impact that is likely to come with continued high emissions of greenhouse gases.”  Though New Jersey has warmed by about 2.3 degrees Fahrenheit over the past century, it is the winter low temperatures that are most important. Nights must get to about 8 degrees below zero to kill the beetles. The New Jersey climatologist’s office calculates that such bitter nights used to happen several times per decade in the state. The last night that cold in the Pinelands was in 1996, and the beetle outbreak was first noticed five years later.

Though global warming usually focuses on high temperatures, the graph shows that there is also an increase in the average nighttime temperatures. Record highsThe coldest nighttime temperatures are the main determinant in the geographic range of bacteria, fungi, insects, and invasive species. Those who do not wish to address the problem of global warming often ignore those small things, one of which is the bark beetle. Besides the economic loss of billions of trees, there is an aesthetic loss in the beauty of the forests. The tree loss contributes to wildfires, problems with water management, and loss of food and habitat for many species that live in the pine forests. Those who claim it will cost too much to reduce our carbon emissions, do not consider the cost of not addressing the issue. The pine bark beetle is an example of but one of the many costly things that should be included in their balance sheets.

(c) 2013 J.C. Moore

Media Bias: Why the Public Is Confused about Climate Change

Mon ,16/12/2013

The Tulsa World article ,”Global warming poll finds broad divide more political than scientific,” attempted to explain why the public and politicians are confused, not only about the issue, but about what scientists think.  Polls of climate scientists find a strong consensus on the issue , with  97 percent of scientists actively engaged in climate research agreeing that man’s activities are the main cause of global warming. Fearing a loss of profit if CO2 is regulated, there has been a well-funded effort to spread doubt about the scientific consensus. And some media sources are willing accomplices.

 The media has helped spread the doubt by treating the issue as a legitimate controversy, when there is very little controversy among scientists. At one time the Tulsa world was courageous enough to point out in an editorial that it was scientists who say that global warming is real and politicians who say that it is a hoax. However, the Tulsa world has changed ownership and the new managing editor has adopted a bias which he calls “reflecting Oklahoma values. “ The Tulsa World often publishes comments from readers in its editorial page, and though there were a number comments reflecting the scientists’ viewpoint, the editors added to the confusion by publishing only two comments from one side, and none representing scientists.

One comment tried to explain away the strong consensus among scientists by claiming that scientists find what they do because of money the research generates. However, climate and weather research is vital to our national interest and would be funded no matter what the scientists found. Climate scientists usually work at universities and government laboratories, where salaries range from $50,000 to $120,000. Research grants are awarded on a competitive basis, and most of the money from the grants goes for research expenses and little to the scientists. Their published results are held to a high peer review standard to ensure that the methodology is sound and the conclusions are consistent with the evidence. The amount of money they get is certainly not worth taking a chance on ruining their reputation and career.

The second comment claimed that the Earth’s systems are just too complicated to understand, and therefore climate scientist can’t know what they are talking about. That is the old Skeptic’s argument that if you don’t understand everything, then you understand nothing. In spite of the complexity, scientists have been able to identify the main factors that affect our climate. Greenhouse gas theory was developed in the 19th century, and after examining the natural and human caused factors that affect our climate, climate scientists have concluded that the main factor in global warming is man’s release of CO2.

The human body is also very complex, but medical scientists have identified a major risk factor to health be smoking. Yet, for many decades, tobacco companies were able to deny the scientific evidence that showed the link between smoking and coronary disease. Climate scientists have identified the major risk factor in climate change to be man’s emission of CO2 and warn of the danger to the environment that sustains us. However, like smokers who ignore their doctors, many people are unwilling to listen to the scientists’ warning. Would the Tulsa World, and other media sources, now be willing to treat the dangers of smoking as a legitimate controversy?

(c) 2013  J.C. Moore


Global Warming: The North Carolina Solution

Wed ,21/08/2013

Comedians and late-night talkshow host have had a lot of fun with North Carolina’s solution to the rising sea levels caused by global warming. The legislature passed a law to deal with it.

HB 819 : North Carolina lawmakers recently passed HB 819, which included a four-year moratorium on the state Coastal Resources Commission authorizing sea-level forecasts to be used as the basis for regulations while the issue is studied. “North   Carolina should not ignore science when making public policy decisions,” Governor Bev Perdue said. And then she ignored science by refusing to veto HB 819, allowing it to come become law. Any time a law forbids scientific research, you can be sure there is a special interest group behind it.

Special interests: A group called NC-20 claims that floodplains should be determined by historic trends which suggest the seas will only rise 8 inches this century, rather than the scientific data which projects three times that . Republican Rep. Pat McElraft explained,“What we have done is ask them to use a blend of models, to use historical data, to use some real science that we can all trust when we start making laws here in North Carolina”. McElraft, who is a former real estate agent, denied that campaign contributions ever influence her. However, the largest industry contributors to McElraft’s campaigns have been the North Carolina Association of Realtors, followed by the North Carolina Home Builders’ Association. And you can be sure that when politicians say “real science”, it is usually to get around acting on what is actually, real science.

Real Science: Scientists have found that the sea levels have been rising in response to thermal expansion of the ocean and the melting of glaciers. The graph below shows that sea levels have been rising about 3.2 mm per year, which is about 14 inches per century:

Sea Rise


The graph above represents the average rise in sea level over the Earth. However, global warming does not cause the sea levels to rise everywhere at a uniform rate and they are rising much more quickly along the Atlantic Coast of the United States. The U.S. Geological Survey recently released a study that shows the East Coast from Cape Hatteras to Boston has already seen a sea level rise three to four times higher than most of the world in the past 20 years, and will likely continue to do so. The North Carolina Coastal Resources Commission’s 13-member panel of scientists conducted a nine-month study and warned in 2010 that sea levels in North Carolina could rise by more than 3 feet by 2100 and threaten more than 2,000 square miles of coastal land.

Enter HB 819: There is some very expensive real estate on the Barrier Islands and along the coast of North Carolina that is only a few feet above sea level. Sea level rise threatens the value of that property and makes it more vulnerable to storm surges from hurricanes. Real estate developers might be prohibited from building –  or rebuilding homes damaged by hurricane Sandy and Irene – if low-lying areas were to be designated as a floodplain by the North Carolina Coastal Resources Commission. As an insurance adjuster in North Carolina explained it, “ NC has dumped the coastal flooded homes on the National Flood Insurance Program for years. They build the homes in a predicted floodplain. Lo, and behold the homes on the coast are flooded. The Feds then have to pick up the tab for NC building homes in known floodplains. They are even today rebuilding homes where they were flooded previously in the exact same spot – in an ocean floodplain.”

It’s a sweet deal, the North Carolina developers and builders profit by building homes in the floodplain, and the federal government picks up the tab when the homes flood. Apparently the legislature is not going to let a little science interfere with that sweet deal.

Note added on 1/15/2015: A recent report in Yale e360 says that the storm destruction/rebuild process is continuing. Along the East after Hurricane Sandy and across the Gulf of Mexico coast in the wake of recent hurricanes, rebuilding has taken place on dozens of vulnerable barrier islands. “This recurring reconstruction places billions of dollars of property at risk  and often means the construction of hugely expensive flood protection and storm-control projects that can harm coastal ecosystems.” The real estate developers profit while the taxpayers are responsible for the risk. In a 2014 report, the National Research Council concluded that barrier islands, as “inherently mobile” and not safe for “human facilities with a fixed position.”

(c) 2013 J.C. Moore



Global Warming: Misguided Comments about the Northwest Passage

Mon ,19/08/2013

There was recently an article about global warming  in the Tulsa World which took an interesting approach to the topic. It was an article from two Earth scientists which started , “As climate researchers from divergent political leanings we regularly hear misguided comments about global warming. To help move the dialogue forward we offer a brief response to the top 10. ”  They went on to agree that the Earth is warming, that carbon dioxide is the main cause, that we are causing undesirable changes in the environment, and that we should leave things as best we can for future generations.

Probably the most relevant quote in the article is, “As climate researchers from divergent political leanings we regularly hear misguided comments about global warming.” Many of those misguided quotes come from anti-science websites like those of Anthony Watts, Roy Spencer, or Steve McIntyre’s. They use a little information which may be true but they do not tell you the rest of the story which puts it into perspective.

For instance, many anti-science web sites make a lot of the fact that the Northwest Passage was navigated around 1936. Satellite pictures show that since 1979, the extent of the Arctic sea ice has declined by about 40%. The claim about the Northwest Passage being open in 1936 is an effort to discount that by trying to show that in 1936he Arctic Ocean was open water. That was certainly not true, as the few early passages made then were with the help of icebreakers. You can get a better idea of how the Arctic Ocean is changing by looking at the actual shipping records:

Commercial Shipping on the Northern Sea Route 5,Table 1

Year    Cargo,Thousands of Tons   Length of Season

1935                246                               93 days

1940                289                              93 days

1950                503                              122 days

1960                1013                            128 days

1970                2400                            140-150 days

1980                4951                            year round for western section

1987                6579                            year round for western section


Source: Derived from figures presented at the Conference of Nordic Navigation Institute, Tromsø, Norway, March, 1992.

The data certainly paints a different picture and it is interesting that none of the anti-science websites bothered to mention it.

You may have also heard one of the many versions of the story that, “the Earth hasn’t warmed in the last 15 years”. The anti-science sites got that from a BBC interview with Phil Jones, director of the British Climate Research Unit (CRU). The BBC interviewer asked Do you agree that from 1995 to the present there has been no statistically-significant global warming?” Dr. Jones repliedYes, but only just. I also calculated the trend for the period 1995 to 2009. This trend (0.12C per decade) is positive, but not significant at the 95% significance level.”  Dr. Jones went on to explain that the result was not “statistically significant” because of the short time period.

Dr. Jones is often quoted but somehow the “statistically significant part” is omitted. You can prove a lot of untrue things about the Earth’s temperature by using using carefully selected or short time periods. For instance, if I were to choose the 16 years from 1982 to 1998, I could show that global warming has gone up by a whopping 0.31°C per decade. That, of course, is not statistically significant either. It takes about 30 years to average out the effects of natural variations and, over the last 30 years, the Earth has warmed about 0.15°C per decade.

The Scientist’s Consensus on Global Warming

Wed ,13/03/2013

Every major scientific society in the world has adopted a statement like that of the American Chemical Society which says,

Careful and comprehensive scientific assessments have clearly demonstrated that the Earth’s  climate system is changing rapidly in response to growing atmospheric burdens of greenhouse gases and absorbing  aerosol particles. There is very little room for doubt that observed climate trends are due to human activities. The threats are serious and action is urgently needed to mitigate the risks of climate change.”

This urgent message continues to be mainly ignored by the public and our politicians. This seems strange as scientist’s trustworthiness is  highly rated by the public, with 84% having a favorable view of scientists. A recent CNN  poll  found that 97% of scientists who are actively engaged in research in climate science agree that global warming is occurring and the primary cause is man’s activities. The strongest consensus comes from the scientists who publish articles on climate science.  A recent peer-reviewed article   in the proceedings of the National Academy of Science found that 97-98% of the scientists agree with the consensus opinion with the strongest agreement coming from those who publish the most in the climate science area. A number of surveys have been taken of different group of scientists with the results shown below:




There is clearly a  consensus among scientists on global warming,  but the public’s opinion  continues to be divided about what scientists think. On the question of whether scientists agree that the earth is warming mostly because of human activity; 45% say scientists agree while 43% say they do not. That is because the 3% of the climate scientists who do not agree with the scientific consensus  receive an inordinately large amount of publicity.  Efforts to  discredit the climate scientist’s consensus usually involve quoting scientists who doubt the opinion of the 97%, then  claiming that destroys the whole consensus. However, those  scientists likely started out in the 3% who doubted the consensus to begin with.

Disagreements in science are usually settled by the evidence. To see what the consensus actually is, you just have to look at the peer-reviewed literature.  James Powell examined the scientific consensus in terms of the number of published articles either agreeing or disagreeing with the consensus. His search of peer-reviewed scientific articles published between January, 1991 and November, 2012 with the keywords “global warming” or “global climate change” produced 13,950 articles. He classified as “rejecting” articles that clearly and explicitly stated that the theory of global warming is false or that some other process better explains the observed warming. Only 24 articles,or 0.17%, rejected the consensus, as represented by the thin red line on the pie chart below.





Of the 24  articles  that rejected the consensus opinion, several  were published by gaming the peer review system. An analysis by John Mashey showed fourteen articles rejecting the consensus opinion were published in Climate Research while Chris de Freitas,  a biased climate change Skeptic, was the editor. Most of the articles claiming the Earth is not warming or that man does not have a major role have been found to have errors or have  been disproven by later research.

Note added on 06/11/2013: A recent paper in the Environmental Science Newsletter in May  found that 97% of the climate scientists support the consensus opinion.
Note added on 07/15/2015: James L. Powell, director of the National Physical Sciences Consortium, reviewed more than 24,000 peer-reviewed papers on global warming published in 2013 and 2014. Only five reject the reality of rising temperatures or the fact that human emissions are the cause, with four of those papers using arguments which had been debunked. Powell found the consensus is now “99.9% plus.”

(c) 2013 J.C. Moore

The Earth Hasn’t Warmed in the Last “X” Years Myth

Wed ,30/01/2013

The title has an “X”, as the number of years varies from 10 to 16 depending on who said it and when. I first heard this myth from George Will when he was attacking John McCain’s stand on global warming during the 2008 presidential campaign. Mr. Will claimed that the Earth’s temperature had not gone up in the last 10 years. When I contacted him for an explanation, he said that it was because 1998 was hotter than any year after that. Strangely, Mr. Will referred to the data from the World Meteorological Organization rather than that from NASA. Mr. Will has no use for the UN, but his statement could only be true if he used the UN data which showed that 2005 was slightly cooler than 1998. NASA’s data shows that 2005 was slightly warmer than 1998, and also that 2007 and 2010 were warmer yet. It’s a little hard to explain how the Earth reached those higher temperatures without  going up, but logic and truth are mostly irrelevant to those who say this.

As the years have gone by, “X” has been increased accordingly and the erroneous statement has been repeated on Skeptic’s blogs, newspaper articles, letters to the editor, op-ed pieces, sites like Yahoo!Answers, and by politicians such as Sen. Inhofe. The number “X” is now up to 16 and when I put “no global warming in past 16 years” in Google’s search engine, I got 114 million hits. It’s a great propaganda piece as it is simple, easily understood, and reduces people’s worry about climate change. Unfortunately, it is very comforting, and very, very wrong. The propaganda has been funded, circulated, and promoted by those who do not want us to address global warming as they have an economic interest in the issue.

So what is the truth of the matter? There are number of natural and man-made factors that affect the temperature of the Earth. The main factors are the amount of solar radiation we receive, volcanic activity, greenhouse gases, and ocean circulations such as El Niño and La Niña. Man’s main contribution falls in the area of greenhouse gases. We are now emitting 30 billion tons of carbon dioxide each year, and the atmospheric concentration of carbon dioxide has gone up about 40% in the last century. That increase and the ensuing feedback loops are the main factors that can be attributed to man. Though there are other contributions, most of the CO2 increase has come from burning fossil fuels.

Probably the best way to see man’s influence on the Earth’s temperature is to subtract out the factors that can be attributed to natural sources and to see what is left. That was done very nicely by climate scientist John Cook in a video which he produced and posted on YouTube. It’s only 2 minutes long, but it shows how the Earth’s temperature has responded to the increasing burden of carbon dioxide in the atmosphere.



If the video doesn’t load, you may access it at: http://www.youtube.com/watch?feature=player_embedded&v=W705cOtOHJ4

Global Warming: The Role of Water Vapor

Sun ,20/01/2013

The Earth’s Temperature: Certainly, the average temperature of the Earth has varied greatly over the last million years, from about 2°C (36°F) during the ice ages to about 15°C (59°F) during the warmer interglacial periods. We are now in an interglacial periodic and the Earth’s average temperature for the last century averages 13.9°C (57°F). Much of the research on the Earth’s temperature has been an attempt to understand the coming and going of the ice ages. We now know that the Earth’s temperature is correlated with the Milankovitch cycles , which affect how much sunlight the Earth receives, but that is not the whole story. That greenhouse gases play a role in warming the Earth was shown by Joseph Fourier in the 1820s. Using the differential equations he developed for heat transfer, Fourier calculated that the Earth, considering its size and its distance from the Sun, should be considerably colder than it actually is. He proposed the Earth must be kept warmer by its atmosphere, which acts much as the glass in a greenhouse. The actual amount of warming that could be attributed to the greenhouse effect was later found from the Stephen Boltzmann law, developed in the early 1900s. If the Earth had no atmosphere, its average temperature would be 33°C  lower, at -19.0°C (-2.2°F). Without greenhouse gases, the Earth would be a frozen block of ice.

Greenhouse Gases: Heat energy leaves the Earth as infrared radiation, which makes up a part of the spectrum that is absorbed by many molecules as they vibrate. As infrared radiation leaves the Earth, it is absorbed then reemitted in all directions, some of it going back toward the Earth where it further warms the Earth. In the 1850’s, John Tyndall’s infrared research found that nitrogen and oxygen, the major components of the atmosphere, do not absorb infrared radiation. He discovered that the molecules responsible for the greenhouse effect were water vapor and carbon dioxide. Water varies from a trace up to about 4% depending on the humidity; carbon dioxide’s concentration was about 0.0028% in Tyndall’s time. In spite of their low concentration, CO2 and H2O both absorb strongly in the infrared region of the spectrum. Also, radiation leaving the Earth must traverse several kilometers of atmosphere, greatly increasing the probability of the radiation being absorbed and readmitted. Carbon dioxide plays a large role for its concentration, as it absorbs strongly in regions of the infrared spectrum where water does not.

Recent research by Kiehl and Tenebreth on the Earth’s energy budget identified five naturally occurring gases that contribute to the greenhouse effect. The gases, along with their contribution in both clear sky and cloudy conditions, are listed in the table.The infrared spectra of the major greenhouse gases can be found at http://chemlinks.beloit.edu/Warming/pdf/greenIR.pdf .

GasesEach of the greenhouse gases has several absorption bands, and there are some regions of the spectrum where the bands overlap, as noted in the table. Once clouds form, the liquid droplets absorbed broadly across most of the infrared region, so cloud formation reduces the contributions of the other gases. Overall, clouds and H2O account for about 75% of the greenhouse effect and carbon dioxide and the other greenhouse gases for about 25%. Some of the coldest nights on Earth are when the humidity is low and the night is still and clear, as the contribution of H20 is reduced far below the 60% given in the table.

The average residence time of a water molecule in the atmosphere is only about nine days. Because precipitation removes water from the air in such a short time, the concentration of water in the air varies from a trace in cold arid region up to about 4% in warm humid regions. The average residence time in the atmosphere of CH4 is 12 years, while the residence times of NO2 and CO2 are more than a century. Gases with long half-lives reside in the atmosphere long enough to become evenly distributed throughout the atmosphere.  Ozone (O3), which has a residence time of a few months, is constantly beingformed in the atmosphere from photochemical processes, many of which are initiated by methane and hydrocarbons.

The Limit of Humidity:  The pressure of the atmosphere is made up of contributions from all the molecules in the atmosphere and the share that each gas contributes is called its partial pressure. The amount of water in the air can be measured by its partial  pressure. There is a limit on the amount of water the air can hold as the humidity becomes 100% when the partial pressure equals the saturated vapor pressure, and the air can hold no more water.


The Saturated Vapor Pressure of Water

The saturated vapor pressure depends only on the temperature and is listed in the table at the right.That limit of water in an air mass can be reached by water evaporating from the surface until the partial pressure reaches the saturated vapor pressure given in the table. Alternatively, the limit can be reached when a mass of air is cooled until its saturated vapor pressure is lowered to the air’s partial pressure. Any further decrease in temperature will cause air to be oversaturated and cloud formation and precipitation is likely to occur. For example, at the equator, where the temperature averages 26°, water will evaporate until it reaches the  saturated vapor pressure of 25.2 mmHg. However, over the Arctic Ocean where the temperature averages 1°C, the air is saturated at 4.9 mmHg. Not surprisingly, the air can hold almost 5.1 times as much water at the equator. Or, on a clear night, when the temperature drops until the saturated vapor pressure is less than the air’s partial pressure, dew will form. The weatherman usually reports the temperature when that will happen as the “dew point”.

 CO2 Controls the Temperature: One of the great mysteries confronting science in the 1800’s was the cause of the ice ages. The role that greenhouse gases had in keeping the Earth warm provided a clue for Arrhenius, who thought that changes in their concentration might be the cause of the coming and going of the ice ages. He set out to find the climate sensitivity, the temperature change expected if the concentration is doubled, for the individual greenhouse gases. Arrhenius understood that the concentration of water vapor in the air was limited by its saturated vapor pressure, which is dependent on the temperature. How then, could an increase in H2O increase the temperature when it was itself limited by the temperature? Carbon dioxide has no such limitation, so Arrhenius turned his attention to finding the climate’s sensitivity to carbon dioxide. Though Arrhenius’s model was simple and the calculations were laborious, he found that doubling the carbon concentration would increase the temperature of the earth by about 5°C. However, the increase in temperature would allow a greater concentration of water vapor in the air which would amplify the warming. Thus, the concentration of CO2 acts as a regulator of water vapor, and ultimately determines the planet’s long-term equilibrium temperature. Recent work using better data and models have found that the climate sensitivity to carbon dioxide is in the range of 3 to 4°C, and carbon dioxide has been proposed as the “control knob” for the Earth’s temperature. Still, water vapor and clouds contribute the most to greenhouse warming, and their contribution is considered to be a positive feedback to the increasing carbon dioxide concentration.

No one in Arrhenius’s day could imagine how the atmosphere’s carbon dioxide concentration could possibly double, and some of Arrhenius’ contemporaries proposed setting some poor quality coal seams on fire to ward off another Ice Age. That proved not to be unnecessary as in 1900 Arvid Hgbom, a volcanologist, calculated that industrial sources were adding CO2 to the atmosphere at roughly the same rate as volcanoes. No one thought much of it as, at that rate, it would take centuries for the amount of CO2 to increase significantly. However, no one imagined that we would burn fossil fuels at today’s rate, putting 30 billion tons of CO2 into the air each year. The amount of carbon dioxide in the air has increased by 40% since Arrhenius’s day, and the temperature of the Earth has increased by about 0.85°C, well in line with Arrhenius’s predictions.

Alternate Theories: There are a number of alternate theories as to why the Earth is warming, and most of the recent ones center around water and clouds, as that is still an active area of research. The most easily dismissed one is that water vapor is responsible for global warming rather than carbon dioxide. Arrhenius showed that was false over 100 years ago, yet some Skeptics are still saying it. Another theory, credited to Svensmark, is that cosmic rays from the stars produce charged particles that promote cloud formation. There is little evidence that the cosmic rays reaching Earth have increased and there are plenty of particulates in the air to seed clouds besides the charged particles.  Another theory is Iris Effect which has been promoted by Richard Lindzen, mostly in op-ed pieces that are not peer-reviewed. His theory is that the earth’s sensitivity to greenhouse gases is low as the increasing  surface temperature at the equator will cause the rising columns of moist air to  rain out more moisture, leaving less to form high ice clouds, known to be a positive forcing. Aside from the fact that it seemed a little unreasonable to claim that more moisture in the air will lead to fewer high clouds, other climate scientists have found significant errors in Lindzen’s published works.

 A recent paper in Remote Sensing by Roy Spencer attributes global warming to cloud formation and it was claimed to “blow a gaping hole in global warming theory.” Its main theory was that clouds were driving global warming, rather than being a feedback mechanism. The paper was quickly refuted by climate scientists by pointing out that Spencer’s model of the Earth’s atmosphere was terribly inadequate. There is also evidence that Spencer’s paper gained publication by gaming the peer review system. Another theory comes from Roger Pielke Jr., who claims that hurricanes and tornadoes are becoming less frequent and destructive, based on an economic analysis of storm damage. Global warming is likely to increase the probability of severe storms, so his work has been used to discount global warming. However, his theories stand in sharp contrast to the number of events and the amounts paid out in storm damage  by Munich Re (the fourth and fifth graphs) , a large secondary insurance company, that analyzed the issue without the benefit of some of Pielke’s assumptions.

The final theory, which would be laughable if it weren’t repeated by many Skeptics to discredit climate science, is that climate scientists have created the CO2 global warming theory purely for their own economic benefit. The greenhouse gas theory was developed, and the main points understood by the end of the 19th century, long before any of today’s climate scientists were even born. Fourier, Tyndall, and Arrhenius established that H2O and CO2 were main factors in warming the earth, with changes in CO2 concentrations being the primary driving force and H2O being a feedback to changes in the CO2 levels. Research since then has confirmed their findings, and their theories have been borne out by the global warming we have experienced since their day. It is hard to believe that any credible scientist would reject such well-established theories.

Note: Much of the historical data in this article came from http://www.aip.org/history/climate/co2.htm

(C) 2013 J.C. Moore