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Chinese Study on the Linkage Between Typhoon Activity and Global Warming
There is a 2008 review article in the Chinese Science Bulletin 53: 2907-2922 entitled, ‘Perspectives on the linkage between typhoon activity and global warming from recent research advances in paleotempestology.’
The Abstract states:
The recent increase in typhoon (tropical cyclone) activity has attracted great interest and induced heated debates over whether it is linked to global warming or only a return to an active phase of the well-known multi-decadal variability. Due to the short instrumental record, our knowledge is quite scarce on the complex processes and mechanism of typhoon generation, development, and evolution, especially for the rare but highly destructive super-typhoons. It is therefore very important to extend the time span of typhoon activity records. Paleotempestology, a young science that emerged in the early 1990s, studies past typhoon activity spanning several centuries to millennia before the instrumental era through the use of geological proxies and historical documentary records. This paper presents a brief review and synthesis on the major research advances and findings of paleotempestology with an emphasis on proxy technique development and applications. The methodology has been evolving from single geologic proxy to multi-proxy techniques by integrating microfossils, sedimentary organic elemental ratios, and stable isotopes, together with typical sedimentary textures and structures, for the diagnosis of storm deposits. A newly-developed proxy technique is employing oxygen isotopes preserved in growing laminae of tree rings, cave stalagmites, and reef corals to diagnose typhoon rainwater impacts. Historical documentary records have been systematically compiled and analyzed to reconstruct the history of typhoon activity in some regions. The extracted typhoon-proxy data show that there does not exist a simple linear relationship between typhoon frequency and Holocene climate (temperature) change. Typhoon activity should have a secular and constant linkage with ENSO fluctuations, in that more typhoons and hurricanes make landfalls in China, Central and North America during La Niña years than El Niño years. This finding is consistent with that derived from recent instrumental data. Shifts in positions of subtropical high exert great influence on storm tracks, but their long-term relationship is still not well understood. All these findings are significant in projecting typhoon trends under global warming scenarios. Future developments in paleotempestology should strengthen the following research fields: (1) proxy generation mechanism and preservation potential, (2) inter-validation of different proxy data, (3) recognition of storm and tsunami deposits, (4) evaluation of paleo-typhoon intensity, (5) numerical modeling, and (6) regional to global scale comparison studies.
CO2Science.org have reviewed the paper:
Reference
Fan, D-D. and Liu, K-b. 2008. Perspectives on the linkage between typhoon activity and global warming from recent research advances in paleotempestology. Chinese Science Bulletin 53: 2907-2922.
Background
The authors write that “the recent increase in typhoon (tropical cyclone) activity has attracted great interest and induced heated debates over whether it is linked to global warming or only a return to an active phase of the well-known multi-decadal variability.”
What was done
To help resolve the debate, Fan and Liu present a brief review and synthesis of the major research advances and findings of paleotempestology, which they describe as “a young science” that “studies past typhoon activity spanning several centuries to millennia before the instrumental era through the use of geological proxies and historical documentary records.”
What was learned
The two researchers’ analysis indicates “there does not exist a simple linear relationship between typhoon frequency and Holocene climate (temperature) change,” especially of the type suggested by climate alarmists. They report, for example, that “on the contrary, typhoon frequency seemed to have increased at least regionally during the coldest phases of the Little Ice Age [our italics].” And they also note that there are typically “more frequent typhoon landfalls during [cooler] La Niña years than during [warmer] El Niño years.”
What it means
Following their own advice about the need “to extend the time span of typhoon activity records” to help resolve the debate over the nature of climate change effects on this important weather phenomenon, Fan and Liu were able to demonstrate that the world’s climate alarmists likely have even the sign of the temperature effect on typhoon activity wrong, as global warming seems to reduce tropical cyclone activity over both the long-term and the short-term.