Brown ocean effect
The brown ocean effect is an observed weather phenomenon where tropical cyclones, which are commonly expected to lose energy when they make landfall, instead maintain strength or intensify over land surfaces.[1] In Australia such storm systems are called agukabams.[2]
One source of the brown ocean effect has been identified as the large amount of latent heat that can be released from extremely wet soils.[3][1] A 2013 NASA study found that from 227 tropical cyclones after landfall, 16 strengthened because of the effect. The press release stated, "The land essentially mimics the moisture-rich environment of the ocean, where the storm originated." Storm systems impacted by the brown ocean effect gave rise to a new sub-category of tropical storm type called Tropical Cyclone Maintenance and Intensification Event or TCMI.[4] Another study concluded that latent surface heat flux from land surfaces actually have the potential to be larger than from the ocean, albeit for brief periods only.[5]
Examples
Tropical Storm Erin is an example of the effect, when the storm intensified over Oklahoma in 2007.[3][1] Another possible case is Tropical Storm Bill, when saturated soil conditions sustained the system for a longer period of time.[6]
References
- 1 2 3 Jeff Masters and Bob Henson (15 June 2015). "Dangerous Flood Potential in Texas, Oklahoma from Invest 91L".
- ↑ Kerry Emanuel, Jeff Callaghan, and Peter Otto (2008). "A Hypothesis for the Redevelopment of Warm-Core Cyclones over Northern Australia". Bibcode:2008MWRv..136.3863E. doi:10.1175/2008MWR2409.1.
- 1 2 Clark Evans, Russ S. Schumacher, and Thomas J. Galarneau Jr. (2011). "Sensitivity in the Overland Reintensification of Tropical Cyclone Erin (2007) to Near-Surface Soil Moisture Characteristics". Bibcode:2011MWRv..139.3848E. doi:10.1175/2011MWR3593.1.
- ↑ Kathryn Hansen (2013). "'Brown Ocean' Can Fuel Inland Tropical Cyclones". NASA.
- ↑ Theresa K. Andersen, David E. Radcliffe, and J. Marshall Shepherd (2013). "Quantifying Surface Energy Fluxes in the Vicinity of Inland-Tracking Tropical Cyclones". Bibcode:2013JApMC..52.2797A. doi:10.1175/JAMC-D-13-035.1.
- ↑ Bob Henson (22 June 2015). "Long-Lived Bill Meets its Demise in Mid-Atlantic".