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Posts Tagged ‘Keeling Curve’

Climate Change: A Letter to Congressman Lucas

Sat ,07/12/2013

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

Global Warming in Pictures

Thu ,01/09/2011

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

As you can see in the graph, the red line shows how intricately the CO2 concentrations and temperatures are related. The CO2 concentration drops to about 180 ppm during the glacial periods and rises to about 290 ppm during the warmer interglacial periods. As the far right of the graph shows, we are now in an interglacial period that began about 6000 years ago. The Milankovitch Cycles predict that Earth should slowly cool for the next 20,000 years, but it is warming instead.  Please note that the concentration of CO2 did not rise above 300 ppm in any previous warmer periods but on the far right side of the graph, the red line indicating the CO2 concentration is now approaching 380 ppm. http://www.daviesand.com/Choices/Precautionary_Planning/New_Data/IceCores1.gif

Current CO2 Levels: In the past, the warming oceans released the CO2 as a natural process. However, man is now putting about 30 billion tons of carbon dioxide into the air each year. Much of it stays there and the Keeling curve below shows how CO2 is building up in air. What might that mean for man? In 2011, the CO2 concentration reached 387 ppm, far higher than it has been for perhaps 15 million  years.

  

 This article explains what the Earth may have been like then: “The last time carbon dioxide levels were apparently as high as they are today — global temperatures were 5 to 10 degrees Fahrenheit higher , the sea level was approximately 75 to 120 feet higher, there was no permanent sea ice cap in the Arctic, and very little ice on Antarctica and Greenland.”

 

Earth’s Temperature: Carbon dioxide is one of the greenhouse gases that warm the Earth. NASA’s graph below shows how its increase is changing the Earth’s temperature. Though the Earth’s mean temperature varies widely from year to year, the graph on the right is a moving average that allows you to see the trend in the temperature much easier.

                                                           htp//data.giss.nasa.gov/gistemp/2010november/fig2.gif

  The effect of particulates, which cool the Earth, can be seen around 1991 when Mount Pinaturbo exploded. The flat place in the graph from about 1940 to 1970 is attributed to particulates generated by World War II, atmospheric atomic bomb testing, and postwar industrialization – before particulate emissions were regulated. Clearly, the Earth is getting warmer.

Record Temperatures: Nine of the 10 hottest years on record occurred in the last decade. The other record-breaking year was 1998. the chart gives the record temperatures for 50 years and the inset for the last last 160 years.

Capture

 


This has led to extreme heat waves  in areas such as Moscow.

 

Moscowjulytempanomaly2010 

 

Effect on the Weather:  According to NOAA, global warming is affecting the El Niño and La Niña ocean currents cycles which affect  the weather patterns in North America.  The cycles are occurring at higher temperatures and are becoming more unpredictable . Changes in ocean currents may be a major tipping point in climate change.

Enso-global-temp-anomalies

Effect on the Earth: Scientist tell us that the increasing CO2 concentration is leading to a warmer Earth, more extreme weather, melting glaciers and polar ice, crop failure, droughts, and wildfires. We have certainly experienced many of those things recently, which should make us think about what effect our activities are having on the Earth. Many of the changes in the Earth are subtle, but here are two of NASA’s pictures that clearly show how the Earth is changing. Between 1979 and 2010, about 30% of the Arctic ice has disappeared.

Current Sea Ice

 This has greatly affected the way of life of the native Inuit who live and hunt on the Polar ice.  While they may adapt, their way of life and culture which sustained them for centuries will be destroyed. The Polar bears, uniquely adapted to live in on the Polar ice, have been put on the threatened species list because their habitat is clearly declining.  As their habitat disappears, so will be the Polar bear. It is something man should think about – as our habitat is deteriorating, also.

 Note: This was posted on 09/01/2011 and updated on 03/06/2013 to include data that was not presented in this more comprehensive collection of pictures and graphs of global warming data.

(c) 2011/ 2013 J.C. Moore

Bits and pieces 10: Global Warming in Pictures

Wed ,31/08/2011

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.

IceAges

 

  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:

 

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.

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.

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.

 

Food Production: The increasing CO2, temperatures, and droughts are expected to decrease food production worldwide.
Figure-28
Extreme Temperatures: Climate scientists now have enough data and computing power to estimate the probability of extreme weather events. The figure below, from a paper by  Hansen et. al.,shows how the distributuion of temperature have varied over the past 60 years. Extremely hot temperatures, those over 3 standard deviations from the mean,  are now over 20 times as probable as for the 1950 – 1980 period and 10 times as probable as for the 1980 – 2010 average.  That means that extreme temperatures that affected less than 1% of the landmass in 1980, now affect almost 10% of the landmass annually.

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

Science, Global Warming, and the Ice Age Mystery

Fri ,31/12/2010

In the early 1800’s, scientists began a search for the cause of the ice ages. That search has led to a discovery of the factors that affect the Earth’s temperature, an understanding of the current global warming, and the solution to the mystery of the ice ages. *

The Data: Science is a way of understanding nature by using observation and reason. Man has always been keenly interested in the weather, but temperature records before 1850 were mostly historical accounts of storms, heat waves, or when bodies of water froze. Thermometers came into use in about 1850, allowing more accurate temperature records. One of the most useful records is NASA’s graph of the Earth’s annual mean temperature, which was compiled from ships logs, weather stations, and satellite measurements. It serves as a scorecard for telling whether the Earth is getting warmer or cooler. NASA’s data has small random variations from year to year because of factors such as sunspots, weather events, ocean currents, and particulates from volcanic eruptions. However, NASA’s graph shows that the Earth’s temperature has clearly trended upward since 1880 – with the exception of a curious plateau from 1945 to 1975 followed by a steeper rise in temperature. The Earth’s mean temperature is now 1.3 F higher than in 1880, and the last decade has been the hottest on record. Any theories or causes put forward to explain the global warming trend must be consistent with the temperature observations.

Possible Causes: Nineteenth century scientists realized from geological evidence that the Earth had gone through many ice ages that alternated with ages of warmer climate. Much of the early research on global warming was a search for the cause of the ice ages. Scientists found that many small variables cause the Earth to warm and cool, but the main three causes are the Sun, particulates, and greenhouse gases.

The Sun’s output seems to have been reasonably stable over the last several million years. Satellite measurements over the last 30 years have shown that while solar radiation has declined ever so slightly during that time, the Earth continued to warm – so clearly changes in the Sun’s output is not the cause of the recent warming. The amount of sunlight the Earth receives does, however, depend on the Milankovitch Cycles. These cycles are small variations in the eccentricity, axial tilt, and precession of the Earth’s orbit that cause the solar insolation, the amount of sunlight the Earth receives, to vary slightly in predictable cycles. Ice core data shows that ice ages tend to occur in roughly 100,000-year cycles that match the timing of the Milankovitch cycles. The temperature between the ice ages and the warm periods, however, are much greater than would be caused by the changes in solar radiation alone. Though a clue to the cause of the ice ages, the Milankovitch Cycles are not the cause of the current warming. They predict a minor cooling trend, which began some 6,000 years ago, will continue for the next 23,000 years. The current warming trend is too rapid and in the wrong direction for the Milankovitch Cycles to be the cause.

Particulates cause the Earth to cool by reflecting incoming sunlight back into space. The role of particulates in cooling the Earth became apparent in 1816 when ash from the explosive eruption of Mt.Tambora caused that year to be called “the year without a summer”, worldwide. The curious plateau in NASA’s temperature record from 1945 to 1975 was primarily caused by particulates from sources such as WW II, atmospheric nuclear testing, and increased industrialization. Research during the early 1970’s showed a huge increase in aerosol particulates from power production, factories, and vehicles – and some alarmists even speculated that we might cause another ice age. Particulates are visible and cause immediate health problems, so by 1980 most industrialized countries had restrictions on particulate emissions. Particulates cannot be the cause of global warming, but reducing their sources can cause the temperature to rise as can be seen in the temperature record after 1980.

The Greenhouse Effect was discovered in the early1800’s when scientists realized that the Earth was kept warm at night because the atmosphere trapped invisible heat rays rising from the surface. Around 1860, John Tyndall identified the invisible rays as infrared radiation and found the main gases that trapped the heat rays to be water vapor and CO2. The amount of water in the air remains relatively constant because of the water cycle. When the humidity is low, water evaporates, and when the humidity gets too high, it rains. However, CO2 has no such restrictions. Since CO2 makes up only a few hundredths of a percent of the air, it was at first dismissed as a possible cause of warming, especially since it was thought that plants and the oceans would absorb any excess.

In 1896, Svante Arrhenius, while still pursuing the idea that variations in CO2 might be the cause of the ice ages, laboriously calculated the effect of cutting the amount of CO2 in the atmosphere by half. He found that doing so would lower the temperature of Europe by 4-5 C, perhaps enough to bring on an ice age. He also found that doubling the amount of CO2 might raise the temperature of the atmosphere by 6-7 C. No one was concerned as Arrhenius’ model of the atmosphere was very crude and it was inconceivable that the amount of CO2 in the air could ever double. Some scientists speculated that man should intentionally add more CO2 to the air to ward off another ice age.

As models of the atmosphere improved, a number of scientists tried to get a better estimate of the effect of doubling the amount of CO2 on the Earth’s temperature, but the increasing complexity of the models made the calculations daunting. A breakthrough came with the development of computers. In 1956, G.N. Plass calculated that doubling the concentration of CO2 in the air would cause a 3 to 4 C increase in the Earth’s temperature. ** Many dismissed his work, as it seemed impossible that CO2, which made up only 0.03% of the air, could have such a large effect on temperature. However, in 1997, J.T. Kiehl found that, under clear sky conditions, CO2 accounted for 26% of the greenhouse effect – with water vapor accounting for most of the rest. More recent research has confirmed their work . Clearly, CO2 could have a significant effect on the Earth’s temperature if it was increasing. But was it?

CO2: In 1900, Arvid Hgbom calculated the amount of CO2 emitted by industrial sources and, surprisingly, found that man was 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, after a protracted heat wave during the 1930’s, Guy Callendar re-examined previous temperature and CO2 measurements and found not only that the Earth was getting warmer, but also that atmospheric CO2 concentrations were increasing rapidly. Callendar’s work was mostly ignored, but a few scientists began monitoring the concentration of CO2 more closely. Their results were sporadic but, by 1958, Charles Keeling had established accurate procedures for measuring atmospheric CO2. His lab was eventually moved to the Mauna Loa observatory, far away from most CO2 sources. His graph showing how CO2 varies with time, now called the Keeling curve, proved to be an important piece of evidence. It showed that the oceans and plants were not taking up CO2 nearly as fast as man was producing it. Over the last century, the atmospheric CO2 concentration has risen from 280 parts per million (ppm) to 385 ppm, a 38% increase, and the Earth’s temperature has risen by 0.8 0C, well in line with Plass’ prediction. The role of CO2 as the major cause of global warming had been convincingly established. There is yet one more piece of evidence that confirms that conclusion.

Ice Ages: It was now possible to solve the mystery of the ice ages. The Milankovitch cycles alone cannot explain the changes in the Earth’s temperature during the cycles, but the process becomes clear if CO2 is included. The ice core data shows that the concentration of CO2 falls to about 180 ppm during an ice age and rises to about 280 ppm during the warm part of the cycle. The changing CO2 concentration happens because the solubility of CO2 in water varies with temperature. In the part of the cycle where the Earth is warmed by the increasing solar radiation, the oceans release CO2, which further amplifies the warming by the greenhouse effect. In the part of the cycle where the solar energy decreases, the oceans cool, the CO2 dissolves again, and another ice age begins. The concentration of CO2 in the atmosphere is the “control knob” for the Earth’s temperature – and we have now turned the knob up to 380 ppm and are moving it even higher. The Earth will surely get warmer.

* Much of the historical data came from this excellent AIP article.

 **  Recent research in the Journal of Climate, covering the last five ice ages, has experimentally confirmed Plass’ estimate of the climate sensitivity.

(C) 2010 J.C. Moore