of f 
7) mapping the distribution of oil on water (resulting from ! 
accidental discharge or natural seeps) and its change with time; 
to r 
8) providing improved, timely, small-scale maps (>1:200,000) of and 
some nearshore areas; and and 
9) monitoring sea ice distributions and their change with time. 
In the case of this latter application, McQuillan and Clough (1973) devo 
undertook a benefit study that indicates a potential saving of many 
fals 
millions of dollars per year in shipping, exploration, and operation. indi 
vell ; : ; inte 
Among the most intriguing results of the Landsat investigations This 
is the recognition of oil on water. Numerous Landsat images exist that noD 
are believed to show the distribution of oil on water, with reflectances subs 
that are in agreement with the physics of the situation, although only R.L. 
one image has been substantiated by other related information. There One 
is, of course, a high potential for use of these observations in envi- form 
ronmental monitoring. In addition, the potential for identifying marine imag 
oil seeps by repetitive observation could provide a new prospecting tool 
for offshore oil exploration (Deutsch, written communication, 1975; 
Otterman and others, 1974; Stumpf and Strong, 1974; and Halbouty, 1976). 
adjo 
i Thes 
Hydrologically, the data are being used for both cperational and hydr 
research purposes. The U.S. Army Corps of Engineers, for example, is scoh 
using Landsat data opeationally, in concert with ground observations, to the 
fulfill the legislative requirement that they inspect each dam in the Land 
United States that could pose a potential flood danger. aed 
Landsat images, used in conjunction with Data Collection System (DCS) orar 
data, are providing useful in providing reliable and timely information to 
water managers in south Florida. In this System, the surface area of 
water, observed in holding areas, is determined from the images, while Pant 
depth information is relayed via the DCS to provide a near constant flow white 
of information on volume of water available for distribution. This The 
information is vital if we are to provide for the preservation of the ort 
unique ecology of the Everglades National Park (Higer and others, 1975). 50.8 
2 i : ; Taqu 
Several major floods have been mapped with Landsat data including the iin 
great floods of the Indus and Mississippi Rivers. The results of these depr 
investigations are: toge 
1) Floods can be mapped with a precision commensurate with gn 2 
1:250,000 scale and the maps are useful for damage assessment when coupled e 
with land use information derived from prior images. The maps are also Pap 
useful for improving flood forecast models, evaluating the effectiveness M 
of flood control structures, and for planning follow-on actions, such as tab! 
redredging; Vand 
2) the extent of flooding may be mapped for perhaps as long as a fhe 
month after crest; a 
16