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the landscape, such as a reduction in glacier lengths and increased
<br />vegetation in colder areas. Far greater changes have occurred during
<br />the time that all current species of animals and plants have been on
<br />the Earth. The relative population sizes of the species and their geo-
<br />graphical distributions vary as they adapt to changing conditions.
<br />The temperature of the Earth is continuing its process of
<br />fluctuation in correlation with variations in natural phenomena. Man-
<br />kind, meanwhile, is moving some of the carbon in coal, oil, and natu-
<br />ral gas from below ground to the atmosphere and surface, where it is
<br />available for conversion into living things. We are living in an in-
<br />creasingly lush environment of plants and animals as a result. This is
<br />an unexpected and wonderful gift from the Industrial Revolution.
<br />ATMOSPHERIC AND SURFACE TEMPERATURES
<br />Atmospheric and surface temperatures have been recovering from
<br />an unusually cold period. During the time between 200 and 500
<br />years ago, the Earth was experiencing the "Little Ice Age." It had de-
<br />scended into this relatively cool period from a wane interval about
<br />1,000 years ago known as the "Medieval Climate Optimum." This is
<br />shown in Figure 1 for the Sazgasso Sea.
<br />During the Medieval Climate Optimum, temperatures were warn
<br />enough to allow the colonization of Greenland. These colonies were
<br />abandoned after the onset of colder temperatures. For the past 200 to
<br />300 years, Earth temperatures have been gradually recovering (26).
<br />Sargasso Sea temperatures are now approximately equal to the aver-
<br />age for the previous 3,000 years.
<br />The historical record does not contain any report of "global
<br />warming" catastrophes, even though temperatures have been higher
<br />than they are now during much of the last three millennia.
<br />The 3,000-year range of temperatures in the Sargasso Sea is typi-
<br />cal of most places. Temperature records vary widely with geograph-
<br />ical location as a result of climatological characteristics unique to
<br />those specific regions, so an "average" Earth temperature is less
<br />meaningful than individual records (27). So called "global" or
<br />"hemispheric" averages contain errors created by averaging system-
<br />atically different aspects of unique geographical regions and by in-
<br />clusion of regions where temperature records are unreliable.
<br />Three key features of the temperature record -the Medieval Cli-
<br />mate Optimum, the Little Ice Age, and the Not-Unusual-Tempera-
<br />ture of the 20th century -have been verified by a review of local
<br />temperature and temperature-correlated records throughout the world
<br />(11), as summarized in Table 1. Each record was scored with respect
<br />to those queries to which it applied. The experimental and historical
<br />literature definitively confirms the primary features of Figure 1.
<br />Most geographical locations experienced both the Medieval Cli-
<br />mate Optimum and the Little Ice Age -and most locations did not
<br />Table 1: Query Yea No Yes/No Twe-Taikd
<br /> ProbabiBty
<br />Wane Climatic
<br />Anomaly $$ 2 7 > 99.99
<br />800-1300 A.D.?
<br />Cold Climatic
<br />~~ly lOS 2 2 > 99.99
<br />1300-1900 A.D.?
<br />20th Century
<br />Warmest in 7 64 14 < O.000I
<br />Individual Record?
<br />Table 1: Comprehensive review of all instances in which temperature or
<br />temperature~omelated records from localities throughout the world pemrit
<br />answers to queries concerning the existence of the Medieval Climate Opti-
<br />mum, the Little Ice Age, and an unusually warm anomaly in the 20th cen-
<br />tury (11). The compiled and tabulated answers confirm the three principal
<br />features of the Sargasso Sea record shown in Figure 1. The probability that
<br />the answer to the query in column 1 is "yes" is given in column 5.
<br />N
<br />E
<br />3 1372 Solar
<br />~, Activity
<br />b 137® ~ 2
<br />U
<br />1 0
<br />`w 13ta 0 0
<br />_ ~
<br />~ ~
<br />Northern Hemhtiphere ~ I
<br />Temperature s ,~
<br />0
<br />U Arctic ~~ yy~ -1
<br />L Temperature ~,a~ Cool -J
<br />~ la I,M,.t.~M'
<br />~ Ghrbai ~
<br />~ 13 Temperature
<br />~ U.S. Temperature Rising
<br />w 12 0.5 °C per Ce=r' ~
<br />L y
<br />Vi 11 C•
<br />d
<br />Sea Level minus 20 Years 6
<br />~^ Rising 7 Inches per Century Z
<br />x ~ 0
<br />8
<br />~g Glacier Shortening ~ 'Pa1i1 ,$
<br />a -4 minus 20 Years ~Foia '~ s w
<br />~ ~ Ircryre 6 U
<br />~ 4 a
<br />a Coal, Oil, and Gas Ire 2 F
<br />~ 1730 1800 1850 1900 1950 28011® ~_
<br />Year ao
<br />Figure 13: Seven independent records - solaz activity (9); Northern Hemi-
<br />sphere, (13), Arctic (28), global (10), and U.S. (10) annual surface air tem-
<br />peratures; sea level (24,25); and glacier length (4) -all qualitatively confine
<br />each other by exhibiting three intermediate trends -warmer, cooler, and
<br />warner. Sea level and glacier length are shown minus 20 years, correcting
<br />for their 20-yeaz lag of atmospheric temperature. Solaz activity, Northern
<br />Hemisphere temperature, and glacier lengths show a Low in about 1800.
<br />Hydrocarbon use (7) is uncorrelated with temperature. Temperature rose
<br />for a century before significant hydrocazbon use. Temperature rose between
<br />1910 and 1940, while hydrocarbon use was almost unchanged. Temperature
<br />then fell between 1940 and 1972, while hydrocazbon use rose by 330%.
<br />Also, the 150 to 200-yeaz slopes of the sea level and glacier trends were un-
<br />changed by the very lazge increase in hydrocarbon use after 1940.
<br />experience temperatures that were unusually warm during the 20th
<br />century. A review of 23 quantitative records has demonstrated that
<br />mean and median world temperatures in 2006 were, on average, ap-
<br />proximately 1 °C or 2 °F cooler than in the Medieval Period (12).
<br />World glacier length (4) and world sea level (24,25) measure-
<br />ments provide records of the recent cycle of recovery. Warmer tem-
<br />peratures diminish glaciers and cause sea level to rise because of
<br />decreased ocean water density and other factors.
<br />These measurements show that the trend of 7 inches per century
<br />increase in sea level and the shortening trend in average glacier
<br />length both began a century before 1940, yet 84% of total human an-
<br />nual hydrocarbon use occurred only after 1940. Moreover, neither of
<br />these trends has accelerated during the period between 1940 and
<br />2007, while hydrocarbon use increased 6-fold. Sea level and glacier
<br />records are offset by about 20 years because of the delay between
<br />temperature rise and glacier and sea level change.
<br />If the natural trend in sea level increase continues for another two
<br />centuries as did the temperature rise in the Sargasso Sea as the Earth
<br />entered the Medieval Warm Period, sea level would be expected to
<br />rise about 1 foot between the years 2000 and 2200. Both the sea level
<br />and glacier trends -and the temperature trend that they reflect -are
<br />-4-
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