On the violation of gradient wind balance at the top of tropical cyclones
Abstract
The existence of physical solutions for the gradient wind balance is examined at the top of 12 simulated tropical cyclones. The pressure field at the top of these storms, which depends on the vertically integrated effect of the warm core and the near surface low, is found to violate the gradient wind balance—termed here as a state of nonbalance. Using a toy model, it is shown that slight changes in the relative location and relative widths of the warm core drastically increase the isobaric curvature at the upper level pressure maps leading to nonbalance. While idealized storms return to balance within several days, simulations of real‐world tropical cyclones retain a considerable degree of nonbalance throughout the model integration. Comparing mean and maximum values of different storms shows that peak nonbalance correlates with either peak intensity or intensification, implying the possible importance of nonbalance at upper levels for the near surface winds.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 12, 2017
- Source ID
- 10.1002/2017gl074552
Entities
People
- Dandan Tao
- David S. Nolan
- Eyal Heifetz
- Fuqing Zhang
- Nili Harnik
- Yair Cohen
Organizations
- California Institute of Technology
- Office of Naval Research
- Pennsylvania State University
- Tel Aviv University
- University of Miami