Earth from Space - Image Information


LOCATION Direction Photo #: ISS018-E-25705 Date: Jan. 2009
Geographic Region: MADAGASCAR
Feature: BETSIBOKA R.


IMAGE
 
Betsiboka River floods, Madagascar-January 2009

Between January 18 and 20, 2009, Tropical Storm Eric swept along the east coast of the island nation of Madagascar. Rain from this storm fell in the catchment of the Betsiboka River, one of the main rivers in northern Madagascar. In an unlikely coincidence, a larger storm, Cyclone Fanele crossed central Madagascar the next day, on January 21, with its outer bands dropping more rain in the Betsiboka basin. By the time this astronaut image was taken on January 30, the river was flooding all along its length.

The impact of the flood can be seen by comparing flood conditions (top) with normal flow conditions (bottom) along a reach of the river. The lower image is a mosaic of two astronaut images taken in late 2003. The main visual differences are the redder color of the river water produced by mud from the eroded red soils of the basin and the greener color of the countryside in the 2009 image, which is related to summer greening of the natural forest vegetation.

The most dramatic changes are the greatly increased width of the river, flooded sand bars within the river, islands shrunken by flooding, and enlarged lakes heavily charged with red mud (indicated as a "muddy lake" on the top image). With time, flood-borne mud sinks out of lake water, and lakes become a characteristically grayer hue. Over time the precise location of the river banks has changed, but such changes probably relate to slower, multi-year changes in the river course.


Images: All Available Images Low-Resolution 597k
Mission: ISS018  
Roll - Frame: E - 25705
Geographical Name: MADAGASCAR  
Features: BETSIBOKA R.  
Center Lat x Lon: 16.4S x 46.6E
Film Exposure:   N=Normal exposure, U=Under exposed, O=Over exposed, F=out of Focus
Percentage of Cloud Cover-CLDP: 10
 
Camera:: N2
 
Camera Tilt: 5   LO=Low Oblique, HO=High Oblique, NV=Near Vertical
Camera Focal Length: 400  
 
Nadir to Photo Center Direction: W   The direction from the nadir to the center point, N=North, S=South, E=East, W=West
Stereo?:   Y=Yes there is an adjacent picture of the same area, N=No there isn't
Orbit Number: 2425  
 
Date: 20090130   YYYYMMDD
Time: 065203   GMT HHMMSS
Nadir Lat: 16.4S  
Latitude of suborbital point of spacecraft
Nadir Lon: 46.9E  
Longitude of suborbital point of spacecraft
Sun Azimuth: 97   Clockwise angle in degrees from north to the sun measured at the nadir point
Space Craft Altitude: 191   nautical miles
Sun Elevation: 58   Angle in degrees between the horizon and the sun, measured at the nadir point
Land Views: BASIN, FOREST, ISLAND  
Water Views: FLOODING, RIVER  
Atmosphere Views:  
Man Made Views:  
City Views:  

Photo is not associated with any sequences


NASA Human
Space Flight
NASA
Home Page
JSC
Home Page
NASA
Image eXchange
JSC Digital
Image Collection
Earth Science &
Remote Sensing

This service is provided by the International Space Station program and the JSC Earth Science & Remote Sensing Unit, ARES Division, Exploration Integration Science Directorate.
NASA meatball logo
ESRS logo