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Published byRandell Foster Modified over 9 years ago
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Part 4 Temperature Rise
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Global Average Temperature Change for the Past 11,300 Years (Holocene) (Science, 8 March 2013: Vol. 339 no. 6124, pp. 1198-1201)
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Temperature Anomaly (1880-2012) Baseline: 1951-1980 Aerosols (tiny particles) Aerosols
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Temperature Anomaly (1880-2011) Baseline: 1951-1980
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Systematic Decadal Shift to Higher Temperatures Relative to 1951-1980
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Temperature Anomalies from 1884 to 2011 Baseline = 1951-1980
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Arctic Air Temperature Anomalies from Proxies (blue) and Observations (red)
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Record High Temperatures in the U.S. are Increasing and Record Lows are Decreasing
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Lead and lag.Carbon dioxide concentrations and averages of temperature proxy records for last deglaciation, as compiled by Parrenin et al. E J Brook, Science, 2013;339:1042-1043 Published by AAAS
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Atmospheric CO 2 and Global Warming Stabilization CO 2 Concentration: Best Estimate (ppm) Lower End (ppm) Upper End (ppm) Equilibrium Global Average Warming (°C) 280 ---- 0 340 320380 1 430 370540 2 440760 3 670 5301060 4 840 6201490 5
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Earth’s Heat Gain During the Past 50 years (10 21 Joules*) Oceans (0-2 km depth) = 245 (91%) Continents = 10.4 (4%) Earth’s Ice = 8.1 (3%) Atmosphere = 6.6 (2%) *A joule is a unit of heat energy
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O CEAN H EAT C ONTENT C OMPARED TO T OTAL L AND, A TMOSPHERE AND I CE H EAT C ONTENT.
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What Global Average Temperatures Become Critical and Catastrophic for Humans? T HE CURRENT BEST ESTIMATE IS 2° C (3.6° F) ABOVE PRE - INDUSTRIAL LEVELS IS CRITICAL. A BOUT 4° C (7° F) IS CATASTROPHIC. T HE E ARTH IS NOW 0.8° C (1.4° F) ABOVE PRE - INDUSTRIAL LEVELS. W HEN THE CO 2 ABUNDANCE REACHES ~430 PPM THE TEMPERATURE ANOMALY WILL EVENTUALLY REACH 2° C. A T ~670 PPM IT WILL EVENTUALLY REACH A ~4° C. T HE CURRENT ABUNDANCE (2013) IS 396 PPM AND RISING AT A RATE OF 2 PPM / YEAR, AND THIS RATE IS INCREASING. A T THE PRESENT ABUNDANCE THE TEMPERATURE WILL EVENTUALLY REACH 1.8° C. E VEN AT TODAY ’ S ABUNDANCE THE TEMPERATURE ANOMALY COULD REACH THE CRITICAL LEVEL BY THE END OF THE CENTURY. (A RMOUR AND R OE, GRL, 38, 2011; A RORA, ET AL., GRL, 38, 2011)
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Probable Temperature Increases for “Low, Moderate and High CO 2 Growth” (numerical data 2011) Increase in Global Average Temperatures 2° C (3.6° F) Critical 3° C (5.4° F) 5.5° C (10° F) Catastrophic
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WHAT IS CRITICAL AND WHAT IS CATASTROPHIC? CRITICAL --- serious drop in food production, serious water shortages, significant sea level rise (~1 m [3 ft]), political unrest, major drop in world economy, major animal extinctions and millions of human deaths. Third-world countries, e.g. Africa, are affected most, including large human migrations. CATASTROPHIC --- mass extinction event (>50% species extinction), major sea level rise, mass starvation, political and economic chaos, ~50% human deaths (>3 billion people). Probably the end of civilization as we know it today.
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