Effects of climate change in Asia

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Past 1,000 years

For full article see Past 1,000 years in Asia

In discussing their approach to the subject of global warming detection and attribution, Krenke and Chernavskaya (2002) state that “an analysis of climate variations over 1000 years should help … reveal natural multicentennial variations possible at present but not detectable in available 100-200-year series of instrumental records.” In this endeavor, they were highly successful, stating unequivocally that “the Medieval Warm Period and the Little Ice Age existed globally.” Studies such as Bao et al. (2003) and Ma et al. (2003), it is evident that for a considerable amount of time during the Medieval Warm Period, many parts of China exhibited warmer conditions than those of modern times. Since those earlier high temperatures were caused by something other than high atmospheric CO2 concentrations, whatever was responsible for them could be responsible for the warmth of today.

Temperature

For full articles see Temperature in Asia and Urban heat islands in Asia

Tan et al. (2004) conclude from their study of a temperature record reconstructed from Beijing Shihua Cave stalagmites that “the synchronism between the two independent sun-linked climate records therefore suggests that the sun may directly couple hemispherical climate changes on centennial to millennial scales.” It stands to reason that the cyclical nature of the millennial-scale oscillation of climate evident in both climate records suggests there is no need to invoke rising atmospheric CO2 concentrations as a cause of the Current Warm Period.

If the development of the significant cold of the worldwide Little Ice Age was driven by a concomitant change in some type of solar activity, which seems fairly well proven by a wealth of real-world data, it logically follows that the global warming of the twentieth century was driven primarily by the reversal of that change in solar activity, and not by the historical rise in the air’s CO2 content. However, as also noted by Xu et al., how small perturbations of solar activity have led “to the observed global warming, what is the mechanism behind it, etc., are still open questions.”

Bashkirtsev and Mashnich (2003) say “it has become clear that the current sunspot cycle (cycle 23) is weaker than the preceding cycles (21 and 22),” and that “solar activity during the subsequent cycles (24 and 25) will be, as expected, even lower,” noting that “according to Chistyakov (1996, 2000), the minimum of the secular cycle of solar activity will fall on cycle 25 (2021-2026), which will result in the minimum global temperature of the surface air (according to our prediction).” Only time will tell if such predictions will prove correct.

Additionally, the urban heat island effect may significantly alter the way temperature is measured. In Shanghai, Chen et al. (2003) evaluated several characteristics of that city’s urban heat island, including its likely cause, based on analyses of monthly meteorological data from 1961 to 1997 at 16 stations in and around this hub of economic activity that is one of the most flourishing urban areas in all of China. Defining the urban heat island of Shanghai as the mean annual air temperature difference between urban Longhua and suburban Songjiang, Chen et al. found that its strength increased in essentially linear fashion from 1977 to 1997 by 1°C.

Commenting on this finding, Chen et al. say “the main factor causing the intensity of the heat island in Shanghai is associated with the increasing energy consumption due to economic development,” noting that in 1995 the Environment Research Center of Peking University determined that the annual heating intensity due to energy consumption by human activities was approximately 25 Wm-2 in the urban area of Shanghai but only 0.5 Wm-2 in its suburbs. In addition, they point out that the 0.5°C/decade intensification of Shanghai’s urban heat island is an order of magnitude greater than the 0.05°C/decade global warming of the earth over the past century, which is indicative of the fact that ongoing intensification of even strong urban heat islands cannot be discounted.

Precipitation

For full article see Precipitation trends in Asia

Evidence from Asia provides no support for the claim that precipitation in a warming world becomes more variable and intense. In fact, in some cases it tends to suggest just the opposite and provides support for the proposition that precipitation responds to cyclical variations in solar activity. Touchan et al. (2003) say “all of the wettest 5-year periods occurred prior to 1756,” while the longest period of reconstructed spring drought was the four-year period 1476-79, and the single driest spring was 1746. Turkey’s greatest precipitation extremes, in other words, occurred prior to the Modern Warm Period, which is just the opposite of what the IPCC claims about extreme weather and its response to global warming.

Extreme Weather

For full articles see Droughts in Asia and Floods in Asia

The history of floods and droughts in Asia provides no evidence of increased frequency or severity during the Current Warm Period.

Cluis and Laberge (2001) analyzed streamflow records stored in the databank of the Global Runoff Data Center at the Federal Institute of Hydrology in Koblenz (Germany) to see if there were any changes in Asian river runoff of the type predicted by the IPCC to lead to more frequent and more severe drought. This study was based on the streamflow histories of 78 rivers said to be “geographically distributed throughout the whole Asia-Pacific region.” The mean start and end dates of these series were 1936 ± 5 years and 1988 ± 1 year, respectively, representing an approximate half-century time span.

Over this period, the two scientists determined that mean river discharges were unchanged in 67 percent of the cases investigated; where there were trends, 69 percent of them were downward. In addition, maximum river discharges were unchanged in 77 percent of the cases investigated; where there were trends, 72 percent of them were downward. Consequently, the two researchers observed no changes in both of these flood characteristics in the majority of the rivers they studied; where there were changes, more of them were of the type that typically leads to less flooding and less severe floods. In the case of the annual minimum discharges of these rivers, which are the ones associated with drought, 53 percent of them were unchanged over the period of the study; where there were trends, 62 percent of them were upward, indicative of a growing likelihood of both less frequent and less severe drought.

References

Bao, Y., Brauning, A. and Yafeng, S. 2003. Late Holocene temperature fluctuations on the Tibetan Plateau. Quaternary Science Reviews 22: 2335-2344.

Bashkirtsev, V.S. and Mashnich, G.P. 2003. Will we face global warming in the nearest future? Geomagnetiz i Aeronomija 43: 132-135.

Chen, L., Zhu, W., Zhou, X. and Zhou, Z. 2003. Characteristics of the heat island effect in Shanghai and its possible mechanism. Advances in Atmospheric Sciences 20: 991-1001.

Cluis, D. and Laberge, C. 2001. Climate change and trend detection in selected rivers within the Asia-Pacific region. Water International 26: 411-424.

Krenke, A.N. and Chernavskaya, M.M. 2002. Climate changes in the preinstrumental period of the last millennium and their manifestations over the Russian Plain. Isvestiya, Atmospheric and Oceanic Physics 38: S59-S79.

Ma, Z., Li, H., Xia, M., Ku, T., Peng, Z., Chen, Y. and Zhang, Z. 2003. Paleotemperature changes over the past 3000 years in eastern Beijing, China: A reconstruction based on Mg/Sr records in a stalagmite. Chinese Science Bulletin 48: 395-400.

Tan, M., Hou, J. and Liu, T. 2004. Sun-coupled climate connection between eastern Asia and northern Atlantic. Geophysical Research Letters 31: 10.1029/2003GL019085.

Touchan, R., Garfin, G.M., Meko, D.M., Funkhouser, G., Erkan, N., Hughes, M.K. and Wallin, B.S. 2003. Preliminary reconstructions of spring precipitation in southwestern Turkey from tree-ring width. International Journal of Climatology 23: 157-171.

Xu, H., Liu, X. and Hou, Z. 2008. Temperature variations at Lake Qinghai on decadal scales and the possible relation to solar activities. Journal of Atmospheric and Solar-Terrestrial Physics 70: 138-144.

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