Extreme Waves Caught With Higher-resolution Modeling
(Click to enlarge) A new study shows high-resolution models capture hurricanes and big waves important for weather predictions, coastal cities, and shipping.
Using decades of global climate data generated at a spatial resolution of about 25 kilometers squared, researchers were able to capture the formation of tropical cyclones, also referred to as hurricanes and typhoons, and the extreme waves that they generate. Those same models, when run at resolutions of about 100 kilometers, missed the tropical cyclones and the big waves up to 30 meters high.
(From Science Daily)– Their findings, published in the Feb. 16 issue of Geophysical Research Letters, demonstrate the importance of running climate models at higher resolution. Better predictions of how often extreme waves will hit are important for coastal cities, the military, and industries that rely upon shipping and offshore oil platforms. And, of course, for surfers.
“It’s well known that to study tropical cyclones using simulations, the models need to be run at high resolution,” said study lead author and postdoctoral fellow Ben Timmermans. “The majority of existing models used to study the global climate are run at resolutions that are insufficient to predict tropical cyclones. The simulations in our study are the first long-duration global data sets to use a resolution of 25 kilometers. It’s also the first time a study has specifically examined the impact of resolution increase for ocean waves at a global climatological scale.”
The other authors on this study are Dáith? Stone, Michael Wehner, and Harinarayan Krishnan. All authors are scientists in Berkeley Lab’s Computational Research Division (CRD).
Climate models work by simulating the exchange of air, water, and energy between the grid “boxes.” In today’s state-of-the-art climate models, these boxes are typically 100 to 200 kilometers wide. That level of detail is good enough to catch the formation and movement of midlatitude storms, the researchers said, because such systems tend to be quite large.
In contrast, tropical cyclones tend to cover a smaller area. While the overall footprint of a hurricane can be broad, the eye of a hurricane can be very compact and well defined, the researchers noted.
Read the full article here: https://www.sciencedaily.com/releases/2017/02/170215092858.htm