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Why is HYSPLIT less useful than CAMEO/ALOHA?
Posted: December 3rd, 2013, 12:51 am
by AnJapan
My full question is: Why is HYSPLIT less useful than CAMEO/ALOHA for transport and dispersion forecasts within 5 km (3 mi) of the release site?
Can someone help me please.
Re: Why is HYSPLIT less useful than CAMEO/ALOHA?
Posted: December 3rd, 2013, 7:52 am
by glenn.rolph
HYSPLIT's minimum time step is 1 minute, so the model cannot be used for transport less than the distance it takes for the pollutant to move in 1 minute. However, keep in mind that the meteorology may not adequately represent the transport/dispersion at the point of release regardless of the model time step. In general, for transport scales less than 1 km, the ALOHA model is recommended.
Glenn Rolph
Re: Why is HYSPLIT less useful than CAMEO/ALOHA?
Posted: December 3rd, 2013, 11:02 am
by KhanhHQ123
There are several reasons why HYSPLIT is not useful for close-range prediction. First, the turnaround time for a custom HYSPLIT run is long enough that a cloud of hazardous material could travel miles from the release site before the output becomes available. Second, HYSPLIT is a Lagrangian puff model designed for applications in wind fields that vary in space and time, while close to the source, plumes generally follow the typical straight-line transport pattern assumed by CAMEO/ALOHA.
HYSPLIT evaluations with field data have not focused on near-field scenarios. In contrast, CAMEO/ALOHA is designed for close-range applications and has been optimized for quick turnaround.
Hope this helps
