With the figure below, we will begin today’s journey about tropical cyclones and climate change. We can see clearly from this figure that western pacific has a high frequency of storms. The intensity (measured by minimum pressure) is lower over cooler water and close to equator, and higher over warmer water. (Mendelsohn et al., 2012)
Knutson et al., 2010 indicates that Atlantic tropical cyclone power dissipation is statistical related to SST over the past 50 years. Figure2 shows this correlation between tropical atlantic ocean SST which has more obvious growth than tropical mean SST and Atlantic power dissipation. The statistical correlation between power dissipation with low frequency variability and local SSTs in northwest Pacific Ocean is much weaker than for Atlantic Ocean. (Knutson et al., 2010)
The relationship between western north Pacific Ocean and North Atlantic Oscillation (NAO) is a significant interdecadal change. Before the 1970s, they are in weak correlation which gradually change to positive and stronger, especially after 1980, the positive correlation is apparent at the 95% level. 1948-1977 is a weak phase of relationship between western north Pacific Ocean and NAO and 1984-2008 is a strong phase which of 0.48 coefficient is obvious at the 99% level. (Zhou & Cui, 2014)
Although the IPCC AR5 indicates that there is no significant trend of tropical cyclone activities in long term. And some researches even argued that global tropical cyclone activities decrease by 12.4 hurricanes per century with different decrease rates in northern hemisphere and southern hemisphere. Tropical cyclones attract lots of attentions from the public, because the huge damage of tropical cyclones influences human beings’ lives deeply. From figure4 (modeling future damage of tropical cyclones in 2100) we can see that the damage of tropical cyclones in different regions almost all increase, especially North America and East Asia. These regions occupy nearly 88% baseline global damage, because of more storms and lots in harm’s way. (Mendelsohn et al., 2012) And the rapid projected growth of economy in Asia and Central Amarica leads to significant growth of damage. Figure5 adds the impact from climate change, whose highest damage point is also North America with 26 billion dollars per year. And East Asia is the second highest damage region of 15 billion dollars per year, and Central America- Caribbean is the third one of 5 billion less than East Asia. (Mendelsohn et al., 2012) The damage is caused by various factors, not only natural factors, but also social factors. For example, the region in harm’s way or hit by tropical cyclones with high intensity are natural factors, whereas the rapid growth in economy or shift of population to coastal areas are social factors. (Mendelsohn et al., 2012)
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