"As Hurricane Gladys neared the southeast coast of the United States (66.5° W, 25.5° N), the high-resolution infrared radiometer (HRIR) scanning system aboard the Nimbus satellite acquired the facsimile at the left [below] of the clouds of the hurricane and the surrounding water masses," according to WILLIAM G. STROUD, of the Goddard Space Flight Center, NASA.

"At the time, Gladys was a fully mature hurricane about 450 miles in diameter. Winds were about 125 mph near the center, with hurricane winds extending 115 miles northward and 85 miles southward. Nimbus I tracked Gladys through its 12-day life as a hurricane.

"The HRIR aboard Nimbus I and II senses radiation from the land, water, and cloud surfaces in the 3.6- to 4.2-micron region of the spectrum. The shades of gray are proportional to the blackbody temperature of the radiating surfaces: the white areas are the tops of the clouds and the coldest areas; the black areas are the surface of the sea, and warmest.

"Below the picture a single scan line passing through the center of the hurricane is displayed. On the left is the nonlinear equivalent-blackbody temperature scale. The scan line is from horizon to horizon, about 5000 km along the surface of the Earth, highly distorted at the edges. At the western (left) horizon the temperatures rise sharply from 210° K of the sky to 290° to 300° K, the approximate sea-surface temperatures. The temperatures at the cloud tops are as low as 210° to 220° K, and the observed temperatures in the eye of Gladys are about 290° K. These temperatures are converted to height above sea level by equating- them to actual temperatures measured by sounding balloons in the vicinity of the storm, as shown on the right. The 290°-K temperature over the eye of the hurricane corresponds to a height of about 2 km; the radiometer probably did not see the surface of the sea through the eye because of the usual high-level, thin, cirrus clouds covering the eye. The main cloud tops were at a height of about 12 km."