# Presentation: 636348

## Mouth of 

**Mouth of **
**the Amazon **
**8 September 2000**

**Notes:**
Flowing over 6450 kilometers eastward across Brazil, the Amazon River originates in the Peruvian Andes as tiny mountain streams that eventually combine to form one of the world's mightiest rivers. This image of the Amazon's mouth was captured by MISR's vertical-viewing (nadir) camera on September 8, 2000 during Terra orbit 3862. The image is approximately 380 kilometers in width.
While the Amazon is surpassed in length by the Nile, it carries the largest volume of freshwater in the world, accounting for nearly 20 percent of the Earth's discharge into the oceans. Millions of cubic feet of water empty into the Atlantic every second, and the effluent is transported to very large distances from shore.

## Fog and Haze 

**Fog and Haze **
**in California’s **
**San Joaquin Valley**
**3 January 2001**

**Notes:**
This illustration features images of southern California and southwestern Nevada acquired on January 3, 2001 (Terra orbit 5569), and includes data from three of MISR's nine cameras. The San Joaquin Valley, which comprises the southern extent of California's Central Valley, covers much of the viewed area. Also visible are several of the Channel Islands near the bottom, and Mono and Walker Lakes, which stand out as darker patches near the top center, especially in the vertical and backward oblique images. Near the lower right of each image is the Los Angeles Basin, with the distinctive chevron shape of the Mojave Desert to its north. 
The Central Valley is a well-irrigated and richly productive agricultural area situated between the Coast Range and the snow-capped Sierra Nevadas. During the winter, the region is noted for its hazy overcasts and a low, thick ground fog known as the Tule. Owing to the effects of the atmosphere on reflected sunlight, dramatic differences in the MISR images are apparent as the angle of view changes. An area of thick, white fog in the San Joaquin Valley is visible in all three of the images. However, the pervasive haze that fills most of the valley is only slightly visible in the vertical view. At the oblique angles, the haze is highly  distinguishable against the land surface background, particularly in the forward-viewing direction. Just above image center, the forward view also reveals bluish-tinged plumes near Lava Butte in Sequoia National Forest, where the National Interagency Coordination Center reported an active forest fire.
The changing surface visibility in the multi-angle data allows us to derive the amount of atmospheric haze. In the lower right quadrant is a map of haze amount determined from automated processing of the MISR imagery. Low amounts of haze are shown in blue, and a variation in hue through shades of green, yellow, and red indicates progressively larger amounts of airborne particulates. Due to the topographically complex terrain, no results are obtained over the Sierra Nevada and Coastal mountains and these areas are shown in black. However, the enhanced haziness of the San Joaquin Valley is evident in this derived product. Within the yellow pixels, the Sun would look about 40% dimmer to an observer on the ground in comparison to its brightness on a much clearer day. 

## Green Summer and Icy Winter in James Bay

**Notes:**
One year ago, in late February 2000, MISR began acquiring Earth imagery. Its "first light" images showed a frozen James Bay in the Ontario-Quebec region of Canada. These more recent nadir-camera views of the same area illuminate stark contrasts between summer and winter. The left-hand image was acquired on August 9, 2000 (Terra orbit 3427), and the right-hand image is from January 16, 2001 (Terra orbit 5757).
James Bay lies at the southern end of Hudson Bay. It is named for the English explorer Thomas James, who first explored the area in 1631 while searching for the Northwest Passage. Visible in these images are some of the many rivers that flow into the bay; starting at the southern tip and moving clockwise on the western side are the Harricana, Moose, Albany, and Attawapiskat. The latter enters the bay just to the west of the large, crescent-shaped Akimiski Island.

## Roof of the World and the Abode of Snow

**14 May 2000**