Jet Stream Velocity in Response to Large Thermal Changes

Large changes in temperature are known to affect atmospheric circulation in a large variety of ways. In the upper atmosphere, bands of westward moving wind circulate the globe, creating high wind speeds while acting as a barrier between hot and cold air. As the jet stream is vital in controlling the balance of Earth's energy and climate, understanding how it may respond to temperature changes is essential. Numerous studies have investigated the effect of anthropogenic temperature change on the jet stream, yet the temperature ranges explored provided insight into a narrow range of less than 5°C, and suggest a continuous increase in the speed of the jet stream as temperature rises. In this study, a larger data range is explored by utilizing the CESM climate model with simulation temperatures starting from 20°C below to 20°C above pre-industrial temperatures. By analyzing extreme climatic changes, the overall pattern of jet stream speed can be determined to be infinitely increasing or exhibit a non-monotonic response. A positive correlation has been observed between large temperature changes and jet stream speed along with more complex changes to the circulation. These insights may help interpret both past climates and potential future conditions while also offering useful comparisons for atmospheric behavior on other planetary bodies.