Journal cover Journal topic
Natural Hazards and Earth System Sciences An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 2.281 IF 2.281
  • IF 5-year value: 2.693 IF 5-year 2.693
  • CiteScore value: 2.43 CiteScore 2.43
  • SNIP value: 1.193 SNIP 1.193
  • SJR value: 0.965 SJR 0.965
  • IPP value: 2.31 IPP 2.31
  • h5-index value: 40 h5-index 40
  • Scimago H index value: 73 Scimago H index 73
Volume 18, issue 3 | Copyright
Nat. Hazards Earth Syst. Sci., 18, 795-805, 2018
https://doi.org/10.5194/nhess-18-795-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.

Research article 09 Mar 2018

Research article | 09 Mar 2018

The influence of sea surface temperature on the intensity and associated storm surge of tropical cyclone Yasi: a sensitivity study

Sally L. Lavender, Ron K. Hoeke, and Deborah J. Abbs Sally L. Lavender et al.
  • Climate Science Centre, CSIRO Oceans and Atmosphere, PMB1, Aspendale, VIC, 3195, Australia

Abstract. Tropical cyclones (TCs) result in widespread damage associated with strong winds, heavy rainfall and storm surge. TC Yasi was one of the most powerful TCs to impact the Queensland coast since records began. Prior to Yasi, the SSTs in the Coral Sea were higher than average by 1–2°C, primarily due to the 2010/2011 La Niña event. In this study, a conceptually simple idealised sensitivity analysis is performed using a high-resolution regional model to gain insight into the influence of SST on the track, size, intensity and associated rainfall of TC Yasi. A set of nine simulations with uniform SST anomalies of between −4 and 4°C applied to the observed SSTs are analysed. The resulting surface winds and pressure are used to force a barotropic storm surge model to examine the influence of SST on the associated storm surge of TC Yasi.

An increase in SST results in an increase in intensity, precipitation and integrated kinetic energy of the storm; however, there is little influence on track prior to landfall. In addition to an increase in precipitation, there is a change in the spatial distribution of precipitation as the SST increases. Decreases in SSTs result in an increase in the radius of maximum winds due to an increase in the asymmetry of the storm, although the radius of gale-force winds decreases. These changes in the TC characteristics also lead to changes in the associated storm surge. Generally, cooler (warmer) SSTs lead to reduced (enhanced) maximum storm surges. However, the increase in surge reaches a maximum with an increase in SST of 2°C. Any further increase in SST does not affect the maximum surge but the total area and duration of the simulated surge increases with increasing upper ocean temperatures. A large decrease in maximum storm surge height occurs when a negative SST anomaly is applied, suggesting if TC Yasi had occurred during non-La Niña conditions the associated storm surge may have been greatly diminished, with a decrease in storm surge height of over 3m when the SST is reduced by 2°C.

In summary, increases in SST lead to an increase in the potential destructiveness of TCs with regard to intensity, precipitation and storm surge, although this relationship is not linear.

Publications Copernicus
Download
Short summary
This study analyses the influence of sea surface temperature (SST) on the track and intensity of tropical cyclone (TC) Yasi and the associated precipitation and storm surge. A set of regional climate model simulations with SST anomalies varying from +4 to −4 °C are analysed and used to force a storm surge model. Increases in SST lead to an increase in the potential destructiveness of the TC (intensity, rainfall and storm surge), although this relationship is not linear.
This study analyses the influence of sea surface temperature (SST) on the track and intensity of...
Citation
Share