Modeling North Pacific decadal variations and their teleconnection patterns

Low-frequency fluctuations of the ocean and atmosphere over the North Pacific on interannual to decadal time scales significantly impact on the weather, climate and even the marine ecosystems in the East Asia and Western North Pacific. However, modeling the North Pacific climate variability remains a challenging task. It is well-known that the variability in the north Pacific is complicated, and the mechanisms behind the climate variability and its teleconnection with other basins still remain unclear. Here, we plan to identify and understand these patterns and variations in the model so as to provide a completed picture of the North Pacific Climate. Empirical orthogonal function (EOF) has been commonly used to identify the leading modes at different horizontal levels, which change phase at annual, interannual to quasi-decadal scale. From top to the surface, the leading EOF mode of 500 hPa is well-known as Pacific/North-American Pattern (PNA). For the SLP pattern, the first EOF mode is known as Aleutian Low (AL) in the Pacific Ocean, and North Atlantic Oscillation (NAO) in the North Atlantic region. At the ocean surface, the corresponding pattern in the Pacific Ocean is well-known for Pacific Decadal Oscillation (PDO) in the mid-latitude and the El Niño Southern Oscillation (ENSO) in the tropics. In the Atlantic basin, Atlantic Multidecadal Oscillation (AMO) is defined as the SST anomalies. AMO also shows the changing phase in time. Furthermore, the second modes of climate patterns SLP and SST also play an important role on modulating the climate variability because they were highly correlated with the change of the ecosystems. The second EOF modes include low frequency oscillations in decadal scales. In the Pacific Ocean, the second mode at 500hPa, SLP and SSH(or SST) are Western Pacific (WP), North Pacific Oscillation (NPO) and North Pacific Gyre Oscillation (NPGO) respectively. We will evaluate the existing climate variability and teleconnection patterns in the North Pacific using latest Atmosphere-Ocean General Circulation Model (AOGCM). This will help us to enhance our current understanding of the North Pacific Climate and improve the climate predictions. Using different model experiments, we are trying to identify the underlying physical mechanisms driving the climate variability and teleconnection. Finally, we anticipate to bridging the low-frequency climate variation to the global climate pattern.