摘要详情
1069 / 2024-09-20 10:19:06
Impacts of climate change on Arctic winter cyclones and impacts on the ocean
Arctic cyclone intensities and frequencies;,West-Central and Atlantic Arctic,IPCC warming scenarios;,Atlantic water inflow and Fram Strait;,Arctic wave climate and extremes
摘要录用
We simulated Arctic climate using a high-resolution implementation of WRF driven by HadGEM-ES2 climate model, following IPCC scenarios RCP 2.6, RCP 4.5 and RCP 8.5. The downscaled results indicate that, by the end-of-century, there are no significant changes in average minimum central pressures or total number of winter Arctic. However, there are significant changes in spatial patterns, with the frequency and vorticity of cyclones tending to increase over the western Arctic. Due to the poleward movement of the polar frontal zone and the increased low-level tropospheric baroclinicity, more cyclones tend to form within the Arctic Basin and migrate to the western-central Arctic. We expect about 40% more cyclone tracks forming and dying in the Arctic Basin under RCP8.5, compared to present climate. But with reduced baroclinicity in the troposphere, there is reduced genesis, frequency, and vorticity of cyclones over the Atlantic Arctic. Moreover, the depths of cyclones show a robust decrease over the Arctic Basin, suggesting weakened eddy kinetic energy. With climate warming, changes in cyclone vorticities and their depths tend to be stronger. Thus, changes in cyclone track density and intensities become more notable with increasing RCPs.
Ocean impacts are significant. Changes in the volume transport of Atlantic water into the Arctic Ocean can affect the Central Arctic heat and mass balance. To understand the impacts of storms on the inflow through Fram Strait, we implemented NEMO ocean model, to simulate decadal variations of the water volume transport through Fram Strait. The simulations suggest that the water inflow tends weaken in the 1960s and 2010s and strengthen in the 1990s. The decadal variation is associated with decadal storm density variability in the Greenland Sea. With more storms near Fram Strait, southerly wind anomalies dominate the Atlantic water pathway, giving increased Atlantic inflow through Fram Strait.
Storms also drive the Arctic Wave Climate. We examined wave parameters across the Arctic, including the marginal ice zone (MIZ), comparing historical data (1980-2009) with IPCC projections for 2070-2099. Using the WAVEWATCH III (WW3) numerical wave prediction model, we simulated the waves incorporating advanced parameterizations for MIZ wave-ice interactions. Our analysis focuses on the extremes in significant wave heights (Hs), mean wave periods (T0), and dominant mean wave direction (MWD), for winters and summers. To estimate changes in future climate scenarios, we assess the extreme wave conditions for 20- and 100-year return periods using standard stochastic methods.
Ocean impacts are significant. Changes in the volume transport of Atlantic water into the Arctic Ocean can affect the Central Arctic heat and mass balance. To understand the impacts of storms on the inflow through Fram Strait, we implemented NEMO ocean model, to simulate decadal variations of the water volume transport through Fram Strait. The simulations suggest that the water inflow tends weaken in the 1960s and 2010s and strengthen in the 1990s. The decadal variation is associated with decadal storm density variability in the Greenland Sea. With more storms near Fram Strait, southerly wind anomalies dominate the Atlantic water pathway, giving increased Atlantic inflow through Fram Strait.
Storms also drive the Arctic Wave Climate. We examined wave parameters across the Arctic, including the marginal ice zone (MIZ), comparing historical data (1980-2009) with IPCC projections for 2070-2099. Using the WAVEWATCH III (WW3) numerical wave prediction model, we simulated the waves incorporating advanced parameterizations for MIZ wave-ice interactions. Our analysis focuses on the extremes in significant wave heights (Hs), mean wave periods (T0), and dominant mean wave direction (MWD), for winters and summers. To estimate changes in future climate scenarios, we assess the extreme wave conditions for 20- and 100-year return periods using standard stochastic methods.
重要日期
-
会议日期
01月14日
2025
至01月17日
2025
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09月27日 2024
初稿截稿日期
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12月14日 2024
注册截止日期
主办单位
State Key Laboratory of Marine Environmental Science, Xiamen University
联系方式
- JKejing GU
- xm******@xmu.edu.cn
- +86*********
