This is an extended caption of the GIF graphics file called BIOS.GIF.  Image
and caption are courtesy of NASA Goddard Space Flight Center.


FIRST IMAGE OF THE GLOBAL BIOSPHERE

This illustration of the global biosphere is part of NASA Goddard Space Flight
Center's program of Earth-science research.  It shows, for the first time, the
patterns of plant life both on the land and in the oceans as observed from
space.  The illustration was produced by combining data from two different
satellites and shows Earth as a complex system, teeming with life.

OCEAN MEASUREMENTS

The ocean portion is a composite of more than 66,000 images collected between
November 1978 and June 1986 by the Coastal Zone Color Scanner (CZCS), which 
flew on the Goddard-managed NIMBUS-7 satellite launched in October 1978.  The
ocean color measurements made by the CZCS indicate the distribution and 
abundance of phytoplankton in Earth's oceans.  Phytoplankton are microscopic
plants that grow in the upper sunlight regions of the ocean and are the 
ultimate food source for most marine life.  Their uptake of carbon dioxide
during photosynthesis may also be a key factor in helping us to better 
understand the role of the oceans in the global carbon cycle.

Red and orange colors indicate areas of high concentrations.  Yellow and 
green represent areas of moderate concentration.  Blue and violet colors
represent the lowest concentrations.

The high phytoplankton concentrations along coasts and other regions where
wind and currents mix the cooler, nutrient-rich waters near the surface, are
often rich with fish and wildlife.

LAND MEASUREMENTS 

The land vegetation image is a composite of three years of data, collected
during 15,000 orbits from the Advance Very High Resolution Radiometer (AVHRR)
flown on the NOAA-7 satellite, launched in June 1981.  The AVHRR measured 
land-surface radiation, which can be a measure of the potential for vegetation
production on land.

The dark green areas (rain forests) show the highest potential for vegetation
growth.  The lighter shades of green highlight tropical and subtropical 
forests, temperate forests and farmlands, and some drier regions such as
savannahs and pampas.  The yellow shades in the United States Midwest show
lower potential.  The great deserts of the world are evident as the lighter
shades of yellow.  The snow and ice covered regions are shown to have no 
productive potential in this image.

This study is part of NASA's multiyear global research program called Mission
to Planet Earth that will use ground-based, airborne, and space-based
instruments to study Earth as a complete environmental system.  Mission to
Planet Earth is NASA's contribution to the US Global Change Research Program,
a multi-agency effort to understand, analyze, and predict better the effect
of human activity on Earth's environment.  Goddard Space Flight Center's 
projects for Mission to Planet Earth include: the Upper Atmosphere Research
Satellite; Earth Probes, such as the Tropical Rainfall Measuring Mission;
the Total Ozone Mapping Spectrometer; and the Earth Observing System, the
most ambitious science mission ever undertaken.