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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

The Skeptic's Guide to the Medieval Warm Period

Sun ,01/04/2012

“How can science claim man is the cause of global warming when the temperature of the Earth was much warmer during the Medieval Warm Period (MWP)?”

The science Skeptics are quite adept at casting doubt on climate science by using clever arguments. One of their favorites is “How can science claim man is the cause of global warming when the temperature of the Earth was much warmer in the last millennium during the Medieval Warm Period (MWP)?”  You don’t really have to be a scientist to figure out that there were no accurate temperature records during the Medieval times and that much of the world was unknown.

The Skeptics usually point to historical records such as those by H.H. Lamb, which describe record heat waves in the known world during the MWP. Skeptics rather ignore the fact that H.H. Lamb was so concerned about the effect of global warming that he founded the Climate Research Unit (CRU) to study the Earth’s temperature records. The scientific questions comes down to  (1) whether the MWP was worldwide, (2) how warm the Earth actually was during the MWP, and (3) what caused the MWP?

Since there were no thermometers and no worldwide network of weather stations during the MWP, scientists have used a variety of proxy data from ice cores, isotope ratios, sediments, geological records, and even tree rings to try to reconstruct the temperatures for the last thousand years. Though there are large uncertainties in proxy records and they require careful calibration, they do show a similar pattern as you can see in the figure below, which is made up of 10 different reconstructions. The black line is the instrumental temperature record.* (See end of article for references.)

 

Though there are wide uncertainties in the proxy temperature records, taken together they form an overall pattern which answers the scientific questions. The proxy records show that that (1) there was a warm period from  AD 1000 to 1200, followed by a cooler period from  AD 1550 to1850  NASA identifies as the Little Ice Age, though it was not a true Ice Age. The record also show that (2) temperatures during the  MWP were quantitatively lower than the temperatures during the latter 20th century. To discover the cause of the MWP, it is necessary to look at another reconstruction.

While studying the cause of the past Ice Ages, scientists have identified the three  main factors which affect the Earth’s temperature, solar irradiance, greenhouse gases (primarily H2O and CO2), and particulates from volcanic activity. Below is a reconstruction of the three main factors controlling the Earth’s temperature. There are many interesting things in the records, but they show (3) the Earth was likely warmer worldwide during the MWP because of the higher solar radiation. It also shows that the solar radiation has been relatively constant during the last century while the other factors, primarily greenhouse gases, have increased.

 

 While it is possible to dispute or argue about the meaning of any of the individual records, it is rather disingenuous to claim that scientists “ have no data” or to dispute the obvious causes of the current global warming. To emphasize that, below is data from the last century, which is based on scientific records. While H20 and clouds accounts for about 75% of the greenhouse warming, their effect has increased only slightly( about 4%) while the amount of carbon dioxide has increased by about 39% in the last century.

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 and they have become 20% more acidic in the last century. Much of the rest stays in the air, and  CO2 is building up in 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. Note:  The effect of particulates from the explosion of Pinaturbo can be seen in the temperature decline from 1991 to 1995.

 

NASA GISS 2010A

 

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. The solar irradiance increased slightly until 1960 and has declined slightly since then.

 

There is the scientific story. Disputes in science are settled by the data. Though Skeptics may dispute the evidence showing the current global warming is caused by man, the question is ” Where is the evidence?”

* References for temperature reconstructions:  The original version of this figure was prepared by Robert A. Rohde from publicly available data from NOAA and the references therein. The article stated: “For the purposes of this comparison, the author is agnostic as to which, if any, of the reconstructions of global mean temperature is an accurate reflection of temperature fluctuations during the last 2000 years. “ The reconstructions used, in order from oldest to most recent publication are:

  • (dark blue 1000-1991): P.D. Jones, K.R. Briffa, T.P. Barnett, and S.F.B. Tett (1998). “High-resolution Palaeoclimatic Records for the last Millennium: Interpretation, Integration and Comparison with General Circulation Model Control-run Temperatures”. The Holocene 8: 455-471. doi:10.1191/095968398667194956
  • (blue 1000-1980): M.E. Mann, R.S. Bradley, and M.K. Hughes (1999). “Northern Hemisphere Temperatures During the Past Millennium: Inferences, Uncertainties, and Limitations”. Geophysical Research Letters 26 (6): 759-762.
  • (light blue 1000-1965): Crowley and Lowery (2000). “Northern Hemisphere Temperature Reconstruction”. Ambio 29: 51-54. Modified as published in Crowley (2000). “Causes of Climate Change Over the Past 1000 Years”. Science 289: 270-277. doi:10.1126/science.289.5477.270
  • (lightest blue 1402-1960): K.R. Briffa, T.J. Osborn, F.H. Schweingruber, I.C. Harris, P.D. Jones, S.G. Shiyatov, S.G. and E.A. Vaganov (2001). “Low-frequency temperature variations from a northern tree-ring density network”. J. Geophys. Res. 106: 2929-2941.
  • (light turquoise 831-1992): J. Esper, E.R. Cook, and F.H. Schweingruber (2002). “Low-Frequency Signals in Long Tree-Ring Chronologies for Reconstructing Past Temperature Variability”. Science 295 (5563): 2250-2253. doi:10.1126/science.1066208.
  • (green 200-1980): M.E. Mann and P.D. Jones (2003). “Global Surface Temperatures over the Past Two Millennia”. Geophysical Research Letters 30 (15): 1820. doi:10.1029/2003GL017814.
  • (yellow 200-1995): P.D. Jones and M.E. Mann (2004). “Climate Over Past Millennia”. Reviews of Geophysics 42: RG2002. doi:10.1029/2003RG000143
  • (orange 1500-1980): S. Huang (2004). “Merging Information from Different Resources for New Insights into Climate Change in the Past and Future”. Geophys. Res Lett. 31: L13205. doi:10.1029/2004GL019781
  • (red 1-1979): A. Moberg, D.M. Sonechkin, K. Holmgren, N.M. Datsenko and W. Karlén (2005). “Highly variable Northern Hemisphere temperatures reconstructed from low- and high-resolution proxy data”. nature 443: 613-617. doi:10.1038/nature03265
  • (dark red 1600-1990): J.H. Oerlemans (2005). “Extracting a Climate Signal from 169 Glacier Records”. Science 308: 675-677. doi:10.1126/science.1107046

(c) 2012 J.C. Moore

Note added on 07/09/2013 : In a new study by the PAGES 2k project, that was  published in Nature Geoscience , 78 researchers from 24 countries worked for seven years on the most extensive climate reconstruction to date of the past 2000 years.  It is based on 511 climate archives from around the world, from sediments, ice cores, tree rings, corals, stalagmites, historical documents and measurements.  Their  graph below confirms the basic “hockey stick” shape of the graph:Pages 2K

 

 

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