One of the more destructive cyclones to emerge from the Northern Hemisphere 2002
summer storm season was Typhoon Sinlaku. Several attributes of this storm event
are portrayed in these data products from the Multi-angle Imaging
SpectroRadiometer. The images were acquired on September 5, when the western
portion of the storm was situated over the Okinawan island chain. Over the next
few days it moved west-northwest, sweeping over Taiwan before making landfall
along China’s Zhejian province on the 7th. The typhoon forced hundreds of
thousands of people from their homes, caused major power outages, and at least
26 people were reported dead or missing before the storm weakened as it moved
While the nature and formation of individual storm events is relatively well
understood, the influence of clouds on climate is difficult to assess due to the
variable nature of cloud cover at various altitudes. MISR’s data products are
designed to help understand these influences. Typhoon Sinlaku is shown at left
as a natural-color view observed by MISR’s vertical-viewing (nadir) camera. The
center panel shows the cloud-top height field derived using automated
stereoscopic processing of data from multiple MISR cameras. Relative height
variations, such as the clearing within the storm’s eye, are well represented.
Areas where heights could not be retrieved are shown in dark gray.
Clouds have a significant influence on the global radiation balance of the
Earth’s atmosphere, and the improvement of climate models requires more accurate
information on how different types of clouds influence Earth’s energy budget.
One measure of this influence is albedo, which is the amount of sunlight
reflected back to space divided by amount of incident sunlight. Bright objects
have high albedo. Retrieved local albedo values for Typhoon Sinlaku are shown at
right. Generation of this product is dependent on observed cloud radiances as a
function of viewing angle and the cloud height field. Over the short distances
(2.2 kilometers) that MISR’s local albedo product is generated, values can be
greater than 1.0 due to the contributions from the sides of the clouds. Areas
where albedo could not be retrieved are shown in dark gray.
The Multi-angle Imaging SpectroRadiometer observes the daylit Earth
continuously from pole to pole, and views almost the entire globe every 9 days.
This image covers an area of about 380 kilometers x 1408 kilometers.
Super Typhoon Choi-wan is formidable in these images, with tightly spiraling bands of clouds and a distinct eye. A vertical cross section of the storm reveals towering clouds and a clear eye surrounded by dense clouds.