2010 Diary week 20
Global warming, climate change and weather extremes
Book Review
Part III of The Breakdown of Climate points out that “In 1958 carbon dioxide levels had reached 315 ppmv. Forty years later, levels were up 50 ppmv. The annual pulse raises the concentration by 7 ppmv in May, from its low in October, a demonstration of seasonal cycles of growth and decay, therefore of photosynthesis and respiration, the trend being ever upward.” “Analysis of air bubbles trapped in the glacier ice of Greenland and Antarctica not only confirms the measurement of carbon dioxide from Mauna Loa, but indicates that the pre-industrial levels of carbon dioxide during the 18th century were around 275 ppmv, and that over the past 160,000 years the levels of the gas have never exceeded 300 ppmv until the mid twentieth century.” “The Vostok core has provided some of the most concrete evidence of atmospheric changes that have taken place over two ice ages and interglacials. Fluctuations of carbon dioxide closely match the rise and fall of temperature.” “Ice cores from Greenland indicate changes of around 50 ppmv in the concentration of carbon dioxide that seem to have taken place in less than 100 years and are associated with abrupt temperature changes of as much as 5ºC.”