Title of the talk: “High-Resolution Coupled Earth System Modeling: An Application – Studies on the Predictability of Tropical Cyclone Genesis”
Abstract of the talk:
Climate science studies clearly reveal that Earth Systems (ESs) and Human Systems (HSs) impact with respect to each other, and HSs produce anthropogenic climate process drivers by greenhouse gas and aerosol emissions. Given that ESs provide resources and environments for human living and development, while global change brings out severe local climate abnormality, what is the adaptive strategy for us local people? Also, two scientific questions are at the front of climate science community: 1) how global change impacts on local weather-climate anomalies, and 2) how local weather-climate perturbations feedback to large scale changes/variations? This talk first shows the development plans of Qingdao National Laboratory for Marine Science and Technology (QNLM) on earth modeling and predictions to address these issues, and discuss significant challenges as well as potential solutions with high-resolution (HR) Earth modeling. Then this talk uses tropical cyclone genesis predictability as an example of climate impact and vulnerability studies to show the important role of HR modeling.
Predicting tropical cyclone (TC) genesis is of great societal importance but scientifically challenging. It requires fine resolution coupled models that properly represent air–sea interactions in the atmospheric responses to local warm sea surface temperatures and feedbacks, with aids from coherent coupled initialization. This talk reports a few sets of high-resolution regional coupled models (RCMs) covering the Asia–Pacific (AP) region initialized with local observations and dynamically downscaled coupled data assimilation to evaluate the predictability of TC genesis in the West Pacific. The AP-RCMs consist of two set resolutions of Weather Research and Forecast–Regional Ocean Model System (WRF-ROMS): 27-km WRF with 9-km ROMS, and 9-km WRF with 3-km ROMS. With finer resolved local sea surface temperatures and wind shear conditions, the enhanced-resolution coupled model improves the predictability of TC genesis. Higher-resolution two-way nesting experiments confirm that resolving much detailed interior structures of a TC and their interactions with the background help sustain the correct intensity and pathway. The forecasts of TC genesis, intensity and moving track could be further improved by improving planetary boundary-layer physics thus better resolving air–sea and air–land interactions.