JPG File 7.91M

Figure 6.19
Movement of dust from the Gobi Desert across the pacific to North America. A. Margin of the dust plume on April 22, 1998 (03:12:52 GMT), four days after the leading edge of the Gobi dust first exited Asia (arrows). The Korean Peninsula appears under cloud down the left side of this north-looking view. The coast of North Korea stretches across the top (dashed line). B. Gobi Desert dust over the northeast Pacific Ocean photographed about 2500 km north-northeast of Hawaii, on April 25, 1998 (20:59:22 GMT). Here dust was transported east (from the center of the horizon toward the lower left) over the Pacific Ocean in association with the jet stream (dense line of cloud). By this date the dust had been transported nearly 5000 km from its source in central Asia. C. Gobi Desert dust formed a prominent haze over the Pacific Northwest on April 27, 1998 (20:58:31 GMT). The densest dust is indicated in this figure (and Figure 20) by two arrows-the left arrow shows a concentration offshore and the upper center arrow shows a concentration over the Columbia Basin of Washington state. The upper right and lower center arrows in this view (and Figure 20) indicate the position of a regional dust front, north of which air over the United States and southern Canada was distinctly hazy. This view was taken from a point over Los Angeles and shows the central valley of California in the foreground. [NASA photographs, Hasselblad camera, 40 mm lens; A. STS090-730-1, center point 40.5N 128.5E, craft nadir 35.3N 132E, altitude 251 km; B. STS090-710-58, craft nadir 38.2N 48.8W, altitude 246 km; C. STS090-739-72, center point 38N 119.5W, craft nadir 35.2N 119.1W, altitude 244 km.]