Tuesday, August 31, 2010

How to find a Hurricane (again)

A year ago I mentioned the excellent visualisation provided by MSNBC's Hurricane Tracker. Here's another: IbisEye, which seems to have been built by the Sarasota (USA FL) Herald Tribune newspaper. Nice presentation and good use of current GOES imagery. Of course there's also the Weather layer in Google Earth 5.2 which also provides a realistic presentation. These online tools synthesizing current and available data don't take away the role of your normal weather service; but with the first Category 4 hurricane (Earl) of the Atlantic season underway and another storm(s) (Fiona) formed/forming they are quick and informative ways to stay informed. Thanks N. Woof.

Friday, August 06, 2010

Remote Sensing of the Forests of Belize

CATHALAC and NASA in collaboration with the Ministry of Natural Resources and the Environment of Belize have completed a remote sensing-based assessment of deforestation and forest cover dynamics of Belize (1.26MB PDF). The study has been validated, and covers 1980 through 2010 (it includes mapping of 1980, 1989, 1994, 2000, 2004, and 2010).

The abovementioned technical paper provides pretty detailed instructions on how to go about doing such a study, and the source and the output data as well as the spectral signatures generated and used in this study are also available. Theoretically, if the forests of other parts of the Caribbean reflect light in similar ways to Belize's forests, the self-same spectral signatures can be used for mapping elsewhere in the Caribbean, for instance.

CATHALAC intends to continue collaboration with Belize's Ministry of Natural Resources and the Environment (specifically specialists at the Land Information Centre and the Forest Department), to catalyze regular, sustained space-based monitoring of Belize's forests. CATHALAC also hopes that the technical paper stimulates the interest of other folks in the Caribbean to pick up something like this - they show that the barriers to conducting such studies are small. Thanks E. Cherrington.

Update: (Thanks K. Lance) Based on this analysis of Landsat satellite imagery for 1980, 1989, 1994, 2000, 2004, and 2010, the validated, national-level assessment indicates that Belize's forest cover has declined from 75.9% in 1980 to 62.7%. Average annual deforestation was estimated at 0.6%, equaling the clearing of some 24,835 acres (9,982 hectares) of forest per year.