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The recent El Nino event has been kind to remote sensors in the Asia Pacific. The reduction in equatorial clouds means that, for the first time in years, space-based remote sensors can get cloud-free views without waiting for months.

Lim Thiam Hock, DigitalGlobe's regional sales manager said that recent projects in the Philippines, Malaysia and China had all been completed far ahead of schedule, much to the delight of clients, because satellites could take advantage of a sudden increase in visibility.

Lim was speaking during the ESRI South Asia users conference held on the Gold Coast in Australia 4-5 March. It was the first outing of Digital Globe's international sales team since the WorldView-2 satellite became operational in January. The satellite will revolutionise the industry, says DigitalGlobe's principal scientist, Kumar Navulur, for a number of reasons. First and most importantly, the satellite has the ability of map vast areas really quickly. It can deliver 1.5 million square km per day, versus the 150,000 sq km of WorldView-1. This is mainly due to improved on-board storage, better data management and a much more capable down-link.

More than that, in addition to the four traditional red, green ,blue and near infra red bands, WorldView-2 has a second NIR band, and new ones called red-edge, yellow and coastal. These extra four bands will make possible a raft of new applications.

The red-edge band is strongly identified with the health of vegetation. The traditional red band responds strongly to green veg, but it lacks discrimination. Now people will be able to do a lot more in terms of differentiating organic matter.

The yellow band is also interesting. It is very strongly sensitive to carbon. It is expected to drive a number of new applications in carbon accounting. For instance, it could be used to map carbon locked up in soil, thus driving a raft of new farming practice in a carbon trading economy.

The coastal band, as its name suggests, will be useful in terms of coastal mapping; it is sensitive to vegetation in the water column and thus a good measure of ocean productivity. However, it is also of interest because it is very sensitive to the atmosphere. It can thus be used to calibrate images.

This is important. One of the main obstacles to the wider use of remotely sensed data is the difficulty of building products that can be moved from place to place. The algorithm required to identify a feature on the ground in a humid and wet city like Kuala Lumpur doesn't work in a dry one, such as Alice Springs.

But Kumar says that this situation can be considerably improved by including the Coastal band in the mix.

ASM Newsletter is distributed by e-mail every week. It reports on events in the spatial industry in Asia and events outside the region which will impact on Asia.