J.C. Moore Online

Current Events from a Science Perspective

 “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 – 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. 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

This is a letter I sent to Congressman Frank Lucas (R – OK) on August 5, 2013. I asked him at his town hall meeting on November 7, 2013 if he had received it, and he could not recall it. It was a 15 page letter which contained anecdotal evidence plus the latest evidence from climate research in full color pictures and graphs. In case he misplaced it, I have reproduced the letter here in hopes he might run across it while looking for my write-up on his town hall meeting. It would seem that this information would be of vital interest to him as he is Chairperson of the Agriculture Committee, charged with the security of our food supply. 

Dear Congressman Lucas,

I’m sure you’re aware of the Pearson drought index which shows that most of Oklahoma, much of the Southwest United States, and much of the Earth’s land area where food is grown  is under moderate to severe drought conditions. It seems that lately the coastal areas of continents have been receiving more rainfall while the interiors have been experiencing more drought. I’ve lived in Oklahoma most of my 70 years and in my recollection, it seems that we are now seeing heavier rains in the spring and longer and more frequent droughts in the summer.

  My family has lived in Oklahoma since statehood and I have a number of anecdotes about how the climate is changing. Our Thanksgiving family photo in 1998 was taken in front of one of my Dad’s apple trees, which still had green leaves. He remarked at the time that he had never seen frost come so late, and he was 88 at the time. A few years ago our plant hardiness gardening zone was changed from a 6 to a 7, acknowledging later frosts and warmer winters. Armadillos are now abundant in Oklahoma, though there were none here when I was growing up.

 Anecdotes do not serve as proof, but they do raise questions about what the theories and evidence is saying. The greenhouse gas theory is solidly based upon the laws of physics. Though greenhouse gases comprise only 1 to 3% of the atmosphere, depending on the humidity, they are responsible for the Earth being about 33°C warmer than its would be without them. It seems reasonable that an increase in the greenhouse gases would cause the Earth to warm. Though water is by far the most abundant greenhouse gas, its concentration in the air is limited by its saturated vapor pressure. Carbon dioxide, though less abundant, absorbs strongly in the infrared and is not restricted in concentration as water is. Studies of the ice ages have identified carbon dioxide and changing solar irradiance as being the main factors in determining the Earth’s temperature.

 We are now putting about 30 billion tons of carbon dioxide into the air each year and measurements show that the concentration in the air is increasing. The increasing partial pressure of CO2 is causing more to dissolve in the oceans, decreasing their pH by about 0.1 pH unit.  That doesn’t sound like much, but the oceans are a carbonate buffer system and that translates into the oceans now being more than 20% acidic, threatening, shellfish, corals, and the plankton which convert much of the ocean’s carbon dioxide back to oxygen.

Biologists have observed that some species are migrating northward and to higher altitudes. There is evidence that glaciers are receding and that ice at the poles is declining. The declining extent of sea ice in the Arctic seems to be affecting the jet stream, which greatly affects our weather patterns. Though it is not possible to prove that global warming is the cause of any one weather event, it likely has an effect on most of the weather events that do occur, since the amount of energy and moisture in the air are the main determinants in weather events.

 There are always uncertainties in scientific measurements, and even greater uncertainties in predictions about the future. It is always possible to dispute any one piece of evidence based upon those uncertainties, but when a large number of independent measurements lead to a similar conclusion, the confidence level increases – but never reaches 100%.  I hope you will examine the evidence presented in the rest of this letter and agree that the preponderance of the evidence shows that we should take some action to address climate change.

 Republicans have a history of being strong advocates for science, environmental responsibility, and sound fiscal policy. Nixon created the EPA, Reagan signed the Montréal protocol limiting fluorocarbons and used cap-and-trade to reduce greenhouse gas emissions blowing into Canada, and archconservative Barry Goldwater once said that, ” The persistent myth that conservation and environmental protection are liberal causes continues to be perpetuated by the media, liberals and many self-professed ‘conservatives’. The truth is that conservation and environmental stewardship are core conservative values”.

 I hope you will examine the evidence presented in the rest of this letter and consider taking a leadership role in addressing the climate change issue in a manner that is consistent with Republican principles. In many ways, the world’s food supply is at risk.

The rest of the letter contained the images and descriptions from this article: http://jcmooreonline.com/2011/08/31/bits-and-pieces-10-global-warming-in-pictures/.

(c) 2013 J.C. Moore

Earthrise over the Moon from Apollo 11.

It is important that we keep in mind those who are heroes and villains  in our efforts to protect the environment. Each year, this site takes a poll to find those most deserving of recognition in the Environmental Hall of Fame and the Environmental Hall of Shame. Nominations are now open for those  awards to those who have most affected the environment by words or action. With the ongoing  debate about  global warming and environmental regulations,  nominees should be easy to find.  Please send  at least one nomination  for  each category by e-mail through the “Contact” link or put it in the comment section . If you would, please include a short reason that your nominee should be chosen and suggest a suitable gift if they win.

Nominations will be taken until June 31st, 2013. The nominees will then be  listed  and this site will conduct a poll to determine the winner in each category.   You may suggest a suitable prize for your nominee. Please be imaginative, as particularly thoughtful or humorous  nominations will  be recognized and published on this site

The 2011 Environmental Hall of Fame Winners  was James Hansen for  playing a pivotal role in delaying a decision on the XL pipeline  whose construction  would greatly accelerate global warming. The 2011 Hall of Shame award went to Halliburton (Cheney),  for the Halliburton clause in the Clean Water Act. This clause provided a loophole that allows the composition of fracking chemicals to remain secret, thanks to Cheney. Past years winners and their gifts were:

Hall of Fame    – Gift    

2011        James Hansen – A massive presence at the 2012 Citizen’s Climate Lobby 

2010        RealClimate.org  – A recommendation from this site. ( Priceless)

2009       Benno Hansen,  ThinkAboutIt Blogger – A Subscription to Science News.

Hall of Shame    

2011        Halliburton (Cheney) –  A big glass of water from a well next to a hydrofracking operation.

2010        Koch Brothers – A petition to the Wizard of Oz for  the grant of a social conscience.

2009       SpaceGuy,  Newsvine Blogger – The movie Wall-E,  representing his view of the future of Earth.

Every person in the world should be concerned about the effect of global warming on the world’s food supply. A good place to begin addressing the issue in the U.S. Congress. Congressman Lucas represents the 3rd district in Oklahoma and is Chairman of the Agricultural Committee. This summer, his district and the entire state of Oklahoma was under severe to extreme drought conditions. But it wasn’t just Oklahoma,  65% of the United States and many of the lands of the Earth where food is grown were also experiencing drought.  Food shortages abroad can pose humanitarian crises and national security concerns. Congressman Lucas has a responsibility to his district, to the United States, and to the world to protect our food supply. If you agree, then please sign the petition .

Congressman Lucas’ campaign ads point out he is trying to keep food prices affordable by opposing government regulation on the size of chicken cages. However, climate change is a much greater threat to food prices and to our food supply. Recent research has shown a direct link between climate change and the heat waves  and  droughts that we have been experiencing. Some may argue that more CO2 is better for plants, but no one doubts that extreme temperatures and droughts are devastating to the world’s food supply. A graph at the bottom of the article projects the  worldwide damage to food  production. As food production has fallen, shortages are beginning to occur, and prices are rising for food and animal feed. If you are worried about food prices, then please sign the petition.

Congressman Frank Lucas was asked at his town hall meeting if he would lead the Agriculture Committee in an investigation of the effect of climate change on our food supply. He said he would consider it, but over a year has passed and no investigation has been undertaken. Besides food prices, climate change will affect the availability of water and food in many parts of the world, particularly those most prone to drought and famine. In this century, water shortages, food shortages, and poverty related nutritional deficiencies will affect close to a billion people globally. We must start now to mitigate the effects of climate change in this century – and the Agricultural Committee is the most important place to start. One voice may be ignored, but a million requests will be heard. Please ask Congressman Lucas to investigate the effect of climate change on our food supply by signing the petition.

Whenever a newspaper reports on an article that confirms man’s role in global warming, a number of outraged citizens usually proclaim on the newspaper’s blog site that the article is wrong. When asked for their source, they often list Wattsupwiththat, Anthony Watt’s blog site.

One recent newspaper article reported on the BEST study, done by a team of climate skeptics funded by Koch industries and led by Dr. Richard Muller, a noted climate skeptic. Dr. Muller’s team analyzed 1.6 billion temperature records in an effort to prove climate scientists wrong. But they didn’t, and Dr. Muller acknowledged it. He reported that global temperatures were probably higher and man’s role was likely greater even than that reported by climate scientists. He also found that the temperature station data, often criticized by skeptics, was accurate – and that the only credible explanation for global warming is the increasing atmospheric CO2 from man’s activities. The  summary of the paper describing the work is now available.

It would seem rather hard to refute Dr. Muller’s work, but one citizen claimed that there was a peer-reviewed journal article that showed that Dr. Muller was wrong. His source was Wattsupwiththat, which did not exactly claim it was peer-reviewed, but certainly left that impression. Here is what it said: “From the told ya so department, comes this recently presented paper at the European Geosciences Union (EGU) meeting. Authors Steirou and Koutsoyiannis, after taking homogenization errors into account find global warming over the past century was only about one-half [0.42°C] of that claimed by the IPCC [0.7-0.8°C].”

However, that isn’t the whole story. The paper was a conference contribution based on a graduation thesis which was submitted to the EGU session, “Climate, Hydrology and Water Infrastructure”. The abstracts are not peer-reviewed and most of Watts’ data was taken from the slides which are also not peer-reviewed. The paper was presented in the wrong session where it was not likely to be heard by experts in the field. There actually was a session on “Homogenization of Data”. An EGU member in attendance noted the paper had errors, and commented, :” It would have been better if this abstract was sent to the Homogenisation Session at EGU. This would have fit much better to the topic and would have allowed for a more objective appraisal of this work. Had I been EGU convener of the Homogenization Session, I would probably have accepted the abstract, but given it a poster because the errors signal inexperience with the topic and I would have talked to them at the poster.” That hardly refutes Dr. Muller’s work.

Another newspaper aticle reported that a link had been shown between extreme temperatures and global warming.  In the past, climate scientists could only say that climate change was increasing the probability of severe weather, heat waves, and droughts. However, a recent paper by James Hansen et. al. established that the probability of extremely hot temperatures, worldwide, is now 10 times as likely as in 1980. Not only did the paper establish a definite link between climate change and extreme temperatures, but the paper was a straightforward statistical analysis that did not rely on theory or climate models. It would seem that that would be difficult to assail.

However, when it was published in the newspaper, a blogger claimed that there was a research paper that disproved the findings, and the trail led to an article  on Wattsupwiththat, panning Hansen’s paper . It referred to an article, Climate Distortion, by Cliff Mass which states, “Their conclusions are demonstrably false and their characterization of the science and statistics are deceptive at best.”  In his article, Mr. Mass  argued: “Now as the earth warms up the temperature variations shown remain like the bell curve…or Gaussian, but the mean should shift to warmer temperatures (see the figure below). The result is that you get more warm extremes and less cold extremes (less cold extremes are not mentioned very often for some reason).”

That would seem reasonable, as an increase in the mean would shift the distribution to the right, meaning more extremely hot temperatures. However, he somehow used this to claim Hansen was wrong. His argument is not clear, and it is certainly wrong, as he ignores the possibility that the variance could change, which would broaden and flatten the distribution. From Hansen’s paper, here is the distribution based on the actual data:

As you can see, the two graphs are quite different. Dr. Mass*, who is  a Professor of Atmospheric Sciences at the University of Washington , does not accept the conclusions of most other climate scientists, and prefers to assign most of global warming to natural variability, a view that Hansen disproved in his paper. Dr. Mass is known for making controversial statements, and though he volunteered his time at for several years as a TV weatherman, he was released for making controversial statements. Mr. Mass apparently rejected Hansen’s paper, as he does not comment on the correct distribution – or that the paper mentions extremely cold temperatures. Climate Skeptics often argue that an extremely cold weather event disproves global warming. However, a similar distribution for the winter months (see paper) shows a significant probability of extremely cold weather events, even though global warming is occurring – meaning the skeptics argument is baseless.

So, Mr. Watts claims a student paper with errors, presented in the wrong session, and is in no way peer reviewed, invalidates two years of work done by a team of climate scientists. You would think that one could not inflate a paper more than that, but actually it can be done. And, Mr. Watts achieved that by promoting Dr. Mass’ article.

* Note on 09/05/2012. The original version of this article did not  give the full credentials of Dr. Mass and the article has been updated with the correct information. Please see the comments for a discussion of this issue.

(c) 2012 J.C. Moore

A large body of scientific evidence, going back to the middle of the 19th century, links the concentration of atmospheric carbon dioxide,  the temperature of the Earth, and the Earth’s climate. Those who study the Earth and its ecosystems have found ample evidence that the climate is changing. The USDA recently acknowledge that fact by shifting the plant hardiness zones for gardeners northward, acknowledging that frosts occur later in the fall and the last freeze in spring occurs earlier. However many people still doubt climate change and point to weather events as evidence.

Theory: Climate scientists would like to clearly establish the link between climate change and extreme weather events, but that is difficult because of the natural variability of the weather.  The link between global warming, heat waves and droughts would seem unquestionable, but it is difficult to prove. Global warming has increased the energy and moisture in the atmosphere, making conditions for severe storms and floods more likely.  In the last century, the Earth’s average temperature has increased by about 0.8°C, increasing the amount of water the air can hold by about 7%.  It is a reasonable conclusion that when it rains, it will rain more and when it snows, it will snow more. So strangely enough, global warming could actually lead to greater snowfall.  (1) However, it has been very difficult to prove, and certainly even more difficult to convince skeptics that that might be the case.

Climate Models: Another approach to linking extreme weather events to global warming has been through the use of climate models. The models take into account the factors that influence climate and weather, and are often used by meteorologists for “future casting” the weather for 10 day forecasts, which is about as long as normal weather patterns last. However, the models may also be used to examine the effect of global warming on the weather events. The models are used to compare the prediction for a weather event assuming that there is no global warming with a prediction of the weather event that includes global warming. In many cases, it can be shown that the weather and rainfall will be more extreme under the global warming conditions. The results are often challenged by climate Skeptics, who claim that the models do not accurately represent the data, or that the models are “falling apart”. The models were developed to fit a century’s worth of the weather and climate data, and there is little evidence to support the Skeptics claims. However climate scientists would like to show a definite link between global warming and weather events to silence those criticisms.

Statistical Evidence: A recent NOAA report, edited by Petersen, et al. (2) , examined 6 extreme weather events that occurred in 2011 and found that there was a link between climate change and the extreme weather event. One of the most interesting reports (3) ,  found that the 2011 heat wave and drought in Texas were 20 times more likely to happen than they would have been in the 1950’s. How did they arrive at that conclusion? A recent paper by Hansen et al.  (4), shows that extreme temperatures are much more likely to occur worldwide than in the 1950’s, and over 10 times as likely to occur as in 1980. As Hansen puts it, the extreme temperatures “which covered much less than 1% of Earth in 1950, now typically covers about 10% of the land area. It follows that we can state, with a high degree of confidence, that extreme anomalies such as those in Texas and Oklahoma in 2011 and Moscow in 2010 were a consequence of global warming because their likelihood in the absence of global warming was exceedingly small.”

Those two papers are important as they have been able to establish a quantitative link between the probabilities of weather events and global warming. More importantly, the link does not depend on theory or on climate models, and relies only on a straight forward statistical analysis of the data. The method depends on computing the normal distribution of the Earth’s temperature anomalies for each decade and then comparing how the distribution of extreme weather events change with time.

Normal distributions:  Before examining how the method works for weather events, it might be useful to examine how it works with something more familiar, like the height of American men. How could we show whether the number of extremely tall men was increasing as time went by?  This could be done by taking a representative sample of men and examining a graph of the normal distribution. We could find the average, μ , and then repeat the process every 10 years to see how the average changed with time. An increase in the average height might indicate that there would be more extremely tall men, but that is not the full story.

Another piece of information that needs to be considered is the variance, or how widely the height of men vary about the mean. The variance is usually measured by the standard deviation , σ, which can be easily calculated from the measurements done to compute the mean. A  graph of the normal distribution  is shown at the right.  “Normal” means that the data has been divided by the total number of men in sample, so that the area under the entire curve represents 100%. That feature is very useful for comparing heights, and it also allows us to associate an area under the curve with  probabilities.

The average height, μ on the graph, is 5’10”, and the standard deviation, σ, is 3 inches. About 95% of the sample falls within 2 standard deviations of the mean, which also says that the probability is 95% that a man selected at random would fall between 5’4″ and 6’4″. Those over 2σ  from the mean, or 6’4″, make up about 2% of the sample and are considered very tall. Finally, those over 3σ  from the mean , over 6’7″, are considered extremely tall and make up only 0.15 %. Michael Jordan and a host of other National Basketball Association players fall into that 3σ category.

How would it be possible to tell whether the incidence of extremely tall men is increasing? One way would be to take height data collected every 10 years, plot the normal distribution, and see how the area of the graphs out past 3σ change. We could not only tell whether there were more extremely tall men, but we could calculate how the probability of finding an extremely tall man changed, just by comparing areas on the graph.

Weather events. Enough data and computing power is now available to calculate normal distributions of temperature data every 10 years for many decades. Having the normal distribution of the temperature data by decade can be used to find whether the probability of extreme temperatures is increasing or decreasing. The Earth’s temperature was fairly stable from about 1950 to 1980, making it a convenient standard for comparing changes. Rather than using temperatures, the graph uses temperature anomalies, which measure how far a temperature reading was above or below average. 

The procedure is similar to the one described for examining the height of men. Hansen, et al. used the Earth’s temperature data to graph normal distributions of the Earth’s temperature anomalies by decade, from 1950 to the present. They found that the distribution of temperature anomalies approximate a normal distribution. 

The results of their work for the summer months show that beginning in about 1970, the mean begins to move to the right toward higher temperatures. It can also be seen that the variance of the data increased and shifted to the right, showing that the probability of extreme temperatures increase greatly from 1950 to 2011.  It can be seen that the number of extreme temperatures, those out past 3 ( meaning 3σ), almost nonexistent in the 1950s, have grown significantly larger in each decade after 1980. A similar graph, using  σ for the last 30 year period (not shown), found the probability of temperatures past 3 sigma is 10 times as great as for the 198o2 to 2010 years.

It should also be noted that the left side of the graph flattens, but that the probability of extremely cool temperatures is not zero. Though  hot temperatures became more probable, that there was still a significant likelihood of cooler temperatures.

Climate Skeptics often argue that an extremely cold weather event disproves global warming. The normal distributions by decade for the winter months is given at the right.  The graph shows the average winter temperatures have increased significantly during the last 30 years and the variance in the temperature has become greater as time progressed. However, the left side of the graph shows there is still a significant probability of extremely cold weather even though global warming is occurring. This means that the skeptics argument is baseless. It is also sometimes argued that extreme snowfalls disprove global warming, but that is also a baseless argument. Extremely cold air can hold little moisture, and it is warmer air, slightly below freezing, that produces the greatest amount of snow. The Inuit know that a warm spell brings a much greater chance of snow.

So there we have it. Climate physics predicts that global warming should cause higher incidences of extreme weather. Climate models find that global warming makes increased rainfall and storms more probable. A straightforward statistical analysis of temperature data not only shows that extreme temperatures are more likely, but has allow climate scientists to calculate how global warming affects the probability of extreme temperatures. A definite link between global warming and extreme weather has been established by the research.

 (1) http://jcmooreonline.com/2011/03/22/the-case-of-global-warming-and-extreme-weather/ 

(2) http://www1.ncdc.noaa.gov/pub/data/cmb/bams-sotc/2011-peterson-et-al.pdf 

(3) http://usnews.nbcnews.com/_news/2012/07/10/12665235-2011-texas-drought-was-20-times-more-likely-due-to-warming-study-says?

4) http://www.pnas.org/content/early/2012/07/30/1205276109.full.pdf+html

(C) 2012 J.C. Moore

The Palmer Drought Index has been used since 1890 to measure drought conditions on a scale of zero (normal rainfall) to -4 (extreme drought).

If you agree that  it is, then please sign the petition below, urging Congress to act.

The author asked Congressman Frank Lucas at his town hall meeting last May if he would consider investigating the effect of climate change on our food supply. Congressman Lucas said he could not commit to it, but he would consider it. However, more than a year has passed and an investigation has not been undertaken. Recently, Congressman Lucas’ campaign ads point out he is trying to keep food prices affordable by opposing government regulation on the size of chicken cages. However, climate change is a much greater threat to food prices and to our food supply.

Heat waves and droughts are becoming increasingly common and are greatly affecting food production and food prices.    During the last 30 years, the Palmer Drought Index, which measures drought severity has fallen as low as -2.2 for the latitudes at which crops are grown. That is  much, much lower than even the dustbowl days.  This is serious. Currently, 64% of theUnited States is under drought conditions. This year’s corn crop is expected to be 10% less than last year’s, which  is  driving up the price of food products and animal feed.  A round bale of hay, normally $20, may be as high as $100 next winter. Last year’s droughts and heat waves reduced the cattle herds by over 3 million animals, and many ranchers are now selling off part of their herds so they can afford to feed the rest next winter. This has kept prices low for now, but the effect will be seen later in the year.

In the past, climate scientists could only predict that climate change was increasing the probability of severe weather, heat waves, and droughts – but they now have enough data and computing power to estimate the probability of extreme weather events. Recently  Stott, et. al.  found that, due to global warming, the heat waves and droughts in Texas and Oklahoma last year were 20 times more likely to happen than in 1950. . Research by Hansen et. al. found the probability of extremely hot temperatures are now 10 times as likely as in 1980. That means that extreme temperatures that affected less than 1% of the landmass in 1980, now affect almost 10% of the landmass annually. What we are experiencing now, will likely be the norm for the future.

If you are concerned about food prices and the future of our food supply, please click on this link, petition on signon.org  , to sign the petition urging Congressman Lucas to lead the Agricultural Committee in an investigation of the effect of climate change on our food supply. Then, please forward a link to the petition to your friends and contacts.

(c) 2012 J.C. Moore

Science is about using observation and reason to understand the physical world. Some people are suspicious of computer models and theories; so here is some of the the basic data in pictures and graphs.

Ice Ages: In the past, the Earth’s temperature has varied from the Ice Ages to the much warmer temperatures of the interglacial periods.  Ice core data gives a good picture of what has happened to the Earth’s temperature in the last half million years, as shown by the blue line. The changing temperatures are attributed to the  Milankovitch cycles,  small variations in the Earth’s orbit that cause the Earth to receive different amounts of sunlight. The Earth becomes slowly warmer during the periods where the solar energy increases. As the Earth begins to be warmed by sunlight, CO2 becomes less soluble in the ocean and the CO2 concentration in the atmosphere increases, which further amplifies the warming since CO2 is a greenhouse gas.  The CO2 did not rise above 300 ppm in any of the the warmer interglacial periods but it is now 398 ppm and rising.

  CO2: Man is now putting about 30 billion tons of carbon dioxide into the air each year. About half of it dissolves in the ocean, making them 20% more acidic, and the rest increases the concentration in the air.

Temperature: CO2 is one of the greenhouse gases that warm the Earth, and NASA’s graph shows how its increase is changing the Earth’s temperature:

.                            NASA GISS Data.

The Sun: The current global warming is often wrongly attributed to an increase in intensity of the sun. The sunspot activity does not show up above the noise in the temperature record above – and the solar irradiance increased slightly until 1960 and has declined slightly since then.

Arctic Ice: Many of the changes in the Earth are subtle but this NASA picture clearly shows  how the Earth is changing:

Arctic ice:  The next two graphs show quantitatively how both the extent and the volume of the Arctic ice is changing.

Arctic ice volume at each years minimum.

Antarctica: Research by Steig and by O’Donnell  show that Antarctica is warming. The warmer oceans result in more snowfall which increases the inland glacier mass, but the erosion of ice by the warmer oceans is causing an overall loss of ice mass.

Antarctic ice mass from GRACE satellite data.

Greenland: The Greenland ice sheets are also beginning to decline.

Ocean Level Rise: The melting ice sheets, melting glaciers, and thermal expansion are causing the oceans to rise by about 3 mm per year which, though it seems small, amounts to an increase in ocean volume of 1190 cubic kilometers/yr.

Rise in Sea Level.

Severe Weather: Warmer temperatures increase both the rate of evaporation and the energy and moisture in the air. This has doubled the incidence of severe weather, floods, droughts, and wildfires.

Permission Courtesy of Munich Re.

Economic Costs: Large insurance companies such as Suisse Re now consider global warming a risk factor as there has been a fivefold increase in billion-dollar weather events in the last 30 years.

Droughts: The Palmer Drought Index below includes most of the continental areas used for food production. Zero represents average rainfall and -4 represents extreme drought. Since 1980, drought conditions have grown worse worldwide, and no one disputes the effect of droughts on food production.

Note : This was posted on 08/31/2011 and  updated on 04/03/2012,08/11/2012, and o2/12/2013.

(c) 2011  J.C. Moore