MEXICO --------- Popocatepetl STS51B-034-0080 Popocatepetl and Ixtaccihuatl Volcanoes, Mexico April 1985 Three individual volcanoes, aligned in a general north-south direction and located about 45 miles (72 kilometers) southeast of Mexico City on the Mexican Plateau, are clearly visible in this near-vertical photograph. The classic radial erosion drainage pattern associated with most stratovolcanoes is very evident around the flanks of all these volcanoes. Upon close inspection, numerous cinder cones can be seen, especially on the plains west of the volcanoes. Two of the volcanoes, Ixtaccihuatl [17 343 feet (5285 meters)] and Popocatepetl [17 887 feet (5452 meters)] have snow-covered summits. Clouds partially obscure Popocatepetl’s large oval crater that measures approximately 2000 feet (600 meters) in diameter and more than 500 feet (150 meters) in depth. Southernmost Popocatepetl is the most famous volcano in Mexico. Its name was derived from an ancient Aztec word meaning "the smoking mountain." Eruptions of the volcano in the mid 1990s put Mexico City and the surrounding communities on alert. The last known eruptions of Popocatepetl before the mid 1990s occurred in the 17th century. The linear feature east of volcano appears to be an airport runway. ------------------------------------------------------------------ Guadalajara STS61B-40-0064 Guadalajara, Mexico November 1985 Sometimes referred to as the ‘Silicon Valley’ of Mexico, the second largest city in Mexico, Guadalajara, can be seen (center of the image) in this south-looking view. Located on a high plain (over 5000 feet-1525 meters) and surrounded by mountains, Guadalajara is the center of a rich agricultural and industrial area. The city is an important mining center and produces chemicals and textiles. Tourism is also an important industry as the city retains much of its Spanish colonial and historic heritage. With its mild, clear, and dry climate, Guadalajara is also a popular health resort. Located 30 miles (48 km) south-southeast of Guadalajara is Lake Chapala (upper left of the image), the largest natural lake in Mexico. Recently, the lake has been plagued by runoff from chemical plants and oil refineries located on its shores as well as an influx of fertilizers and pesticides from the surrounding agricultural lands. ------------------------------------------------------------------------------ MexicoCity 1B-40-0065 Mexico City, Mexico November 1985 Although this photograph of the metropolitan Mexico City area is not very aesthetically pleasing because of substantial air pollution (hazy conditions, with the heaviest concentration visible northwest of the city), some street patterns can be seen at several points throughout the city. Manmade features also include two very large, dark shapes near the center of the photograph (one feature, circular; the other, rectangular). The rectangular shape is a water reservoir, and the circular feature appears to be a water holding facility (later imagery shows that this feature is now dry). The vegetated slopes (dark areas) on the surrounding volcanoes show the radial drainage patterns that are characteristic of most volcanoes throughout the world. Some clouds obscure the volcanic peaks located east of the city; however, the snow-capped peak near the town of Chiautzingo is visible. Mexico City presently has the world’s second-largest metropolitan population with 22.5 million people. Some demographers have forecast an astounding total of between 40 and 50 million residents for greater Mexico City by 2010. In any case, Mexico City will become the world’s largest single population center by the year 2000, surpassing metropolitan Tokyo. It is also noteworthy that the Mexico City region is part of the Ring of Fire (volcano-earthquake zone) that encircles the Pacific Ocean. Thus, this entire area is very susceptible to earthquakes and volcanic activity. -------------------------------------------------------------------------------------- ColimaMassif STS61C-31-0035 Colima Massif, Mexico January 1986 The smoking Colima Volcano (center of the photograph, with the direction of its plume flowing west to east) can be seen in this near-vertical photograph. The volcano, which is more than 13 990 feet (4264 meters) above sea level, is part of a larger structure, the Colima Massif, which is visible above it. These mountains are about 75 miles (120 kilometers) south of Guadalajara (the city is not on the photograph). Colima has been Mexico’s most active volcano, with a total of 49 recorded eruptions since 1560. Light brown ash covers the summits of both peaks. The dark green forested regions cover the flanks of the massif and turn to a lighter green over the agricultural region at the base of the massif and throughout the surrounding valleys. To the north of the Colima Massif, the small city of Guzmán and a small lake can be seen. The canyon of the Tamazula River is visible running north-south to the east of the Colima Massif. To the southwest of the Colima Volcano, the canyon of the Comala River can be seen. High, thin cirrus clouds extend northward just to the west of the Colima Massif. ------------------------------------------------------------------------------------------ MexicanPlateau STS61C-32-2 Mexican Plateau (Mexico City Area), Mexico January 1986 The Mexican Plateau covering most of north-central Mexico is a rugged, arid-to-semiarid tableland with an average elevation of 6000 feet (1825 meters) above sea level. This photograph reveals the southern end of this large plateau with its highest elevation of near 8000 feet (2435 meters). The Mexico City Basin is immediately west of three large, north-south-oriented volcanoes (center of the photograph). Snow-covered at its 17 887-foot (5450-meter) summit, Popocatepetl Volcano is the southernmost and highest of these three volcanoes. The single volcano east of this trio is Malinche Volcano, with the rim of its caldera measuring in excess of 14 600 feet (4450 meters) above sea level. The major air stagnation and pollution problems that plague the Mexico City Basin are easily understandable given the physiography of mountainous terrain and volcanic peaks encircling three-quarters of the basin and the massive population within. In l994, Mexico City had a population of more than 22 million, making it the second most populous metropolitan area on Earth. Some demographers predict that Mexico City will have 40 to 50 million people by 2010. ------------------------------------------------------------------------------------------- InternationalAmistad STS034-074-101 International Amistad Reservoir and Del Rio, Texas, U.S.A. October 1989 Located on the Rio Grande in southwest Texas at the Texas-Mexico border, the International Amistad Reservoir was completed in 1969 as an international flood control project, which can be seen in this north-looking, low-oblique photograph. In the photograph two rivers are visible as they enter the International Amistad Reservoir—the Pecos River northwest of the lake and Devils River to the north. The dam and reservoir support the surrounding region—both Mexico and Texas—with hydroelectric power for municipalities and industry and irrigation water for agricultural crops. Southeast of the dam and barely discernible in the photograph is the small city of Del Rio, Texas. A port of entry to the United States from Mexico, Del Rio is the marketing and distribution center for the region. Agriculture is the main industry in the area, with products including alfalfa, truck crops, and fruits; sheep grazing and wool production are also important. Laughlin Air Force Base, a major jet training command located east of the city, is another major employer in the region. ------------------------------------------------------------------------------------------ TorreoonMexico STS038-086-006 Torreóón, Mexico November 1990 Torreóón, with an estimated population of 250 000, is located on the arid-to-semiarid plateau of north-central Mexico approximately 150 miles (240 kilometers) west of Monterrey. The Torreóón metropolitan area includes the smaller cities of Gómez Palacio and Lerdo, which cluster at the mouth of the Nazas River, parts of which are seen northeast and southwest of the urban area. Visible are several infrastructure features—the airport northeast of Torreóón; several roads and railroads; the more highly reflective commercial and industrial section of Torreóón; and a grid street pattern. Outside the urban area, cultivated agricultural fields abound; cotton and wheat are the two main crops grown in the region. During the mid-1900s, this basin was a major cotton-growing area of Mexico. Large mechanized, irrigated farms were developed by tapping into the once-abundant deep wells for ground water; however, in recent decades, farmers have depended on more meager supplies of surface water for irrigation. This region generally receives less than 20 inches (50 centimeters) of precipitation annually. Torreóón is a major railroad center, especially for north-south traffic through Mexico. --------------------------------------------------------------------------------------------- NorthwestMexico TS040-073-054 Northwest Mexico and Southern California, U.S.A. June 1991 Rugged mountains along the spine of Baja California, the deep blue water of the Gulf of California (also known as the Sea of Cortez), and the deserts of northwestern Mexico and southern California highlight this photograph. This southerly view provides an excellent panorama extending from the Salton Sea in the Imperial Valley of southern California almost to the southern tip of Baja California. Human imprint on this landscape is primarily found along the rivers and their floodplains, where intensive irrigated agriculture exists. The Colorado River, with its cultivated field patterns (darker areas), can be seen to flow from the north toward the southwest and finally to empty into the broad delta at the center of the photograph and to enter the northern end of the Gulf of California. The international border between the United States and Mexico can be identified by the differences in land management, farming practices, and sizes of fields. The border is the east-west straight line approximately 35 miles (56 kilometers) south of the Salton Sea. The Altar Desert is the arid-looking area with no visible vegetation east of the mouth of the Colorado River. ----------------------------------------------------------------------------------------- GuadalupeIsland STS043-076-061 Guadalupe Island, Mexico August 1991 The elongated, volcanic island of Guadalupe (latitude 29 degrees north) is located in the Pacific Ocean approximately 180 miles (290 kilometers) off the coast of west-central Baja California, Mexico. The island is an extinct volcano with a maximum elevation of approximately 4500 feet (1370 meters) above sea level. The photograph illustrates the blocking impact that the elevated terrain can have on low stratus clouds as the clouds move southeastward. The island creates a "cloud wake" downstream (leeward side) of the island, a rather common phenomenon when low stratus clouds pass islands that have adequate elevations to form an impediment to the clouds’ normal flow. The Mexican Government has established the island as a wildlife preserve, especially for the protection of elephant seals. -------------------------------------------------------------------------------------- FalconReservoir TS056-077-057 Falcon Reservoir, Texas, U.S.A. April 1993 Falcon Reservoir, a dammed lake on the Rio Grande operated jointly by Mexico and the United States, is used for irrigation, electric power, and recreation. Barely discernible are Laredo and its Mexican counterpart, Nuevo Laredo (lower right corner). Because it receives less than 20 inches (8 centimeters) of rainfall annually, this semiarid area is identified as the Arid Plains. Visible (top of photograph) are the darker outliers of the more massive Sierra Madre Oriental range of northeast Mexico. ------------------------------------------------------------------------------------------- LowerRio STS056-077-058 Lower Rio Grande Valley, Texas, U.S.A. April 1993 Featured in this photograph is the east-flowing Rio Grande as it disappears southeast of Falcon Reservoir, southeast of which is M. R. Gomez Reservoir on the Mexican side of the border. The highly reflective area on the United States side of the Rio Grande (middle of photograph) shows relatively large, rectangular cultivated fields that produce a variety of crops grown on the flat, fertile, irrigated fields on the Rio Grande floodplain and delta. The areas unsuitable for agriculture consist of dry, sandy soils; scrub trees; sparse grass; and cactus. Many sand dunes are covered by vegetation that stabilizes some of the sand. A small section of the Laguna Madre and South Padre Island are visible (upper right corner). --------------------------------------------------------------------------------------- LakeChapala STS059-91-29 Lake Chapala, Mexico April 1994 Lake Chapala, the largest lake in Mexico, is visible (center of photograph) in this low-oblique, southwest-looking photograph. The lake, set in a shallow depression in Mexico's central plateau, covers 650 square miles (1684 square kilometers), is 50 miles (80 kilometers) long, and is 8 miles (13 kilometers) wide. Lake Chapala is fed by the Lerma River, which enters the east end of the lake (point of land extending into the lake), and is drained by the Grand Santiago River (not visible in the photograph). In the past, Lake Chapala was a popular scenic resort area and fishing center. Since the early 1950s, the water levels in the lake have been receding at an alarming rate because of increased industrial use, agriculture in the surrounding valley (field patterns visible in the photograph), and a decreased flow of water into the lake from the Lerma River caused by field irrigation upstream. Over the last three decades, runoff from fertilizers and pesticides used on agricultural fields and discharges into the lake from chemical plants, oil refineries, and industrial plants have heavily polluted the lake. Guadalajara (gray area north of the western end of the lake) and small lakes (west of the lake) are visible. -------------------------------------------------------------------------------------------- LaMochis STS060-101-053 La Mochis Area, Mexico February 1994 The color infrared image helps to identify the extensive land area that is being used for commercial agriculture along this coastal section of northwest Mexico. Notice the sizeable, angular field patterns (red colors map the extent of healthy green plants) that are widespread across the dry coastal plain of Sinaloa State. La Mochis, visible near the center of the image, has been a boomtown since the 1950’s when the rapid growth of irrigated agriculture started to take in this semiarid region of northern Mexico. Wheat, cotton, soybean, oilseeds, and winter vegetables, especially tomatoes are among the main crops grown. Low mountains (darker, more textured-looking landscape) can be discriminated along the coast (bottom center) and north of the Fuerte River (top center). The dark-looking, uniform feature south of La Mochis is Ohvira Bay, one of many bays that indent this section of coastline in northwest Mexico. The lighter colored landscape inland from the coast shows poorly drained topography that contains virtually no permanent vegetative cover. ----------------------------------------------------------------------------------------- MonterreyMexico STS062-151-377 Monterrey, Mexico March 1994 Monterrey, capital of Nuevo Leon and Mexico’s third largest city (with an estimated 1990 population of 2.5 million), has long been the country’s leading industrial center and the principal railroad hub for northeast Mexico. Power line rights-of-way, railroads, and highways can be seen in this near-vertical photograph. Field patterns are visible in the broad valleys east of metropolitan Monterrey. The north-south-trending, folded Sierra Madre Oriental Mountain Range is a series of elongated limestone ranges forming the eastern rim of the elevated Mexican Plateau. The mountains play a key role in Monterrey’s environment; for example, severe air pollution problems can develop when air stagnation occurs. Ridges in this mountain range vary from 7000 to 8000 feet (2000 to 2400 meters) in elevation, with some peaks reaching 13 000 feet (4000 meters). The ridges and valleys are the result of geologic folding of bedrock and are similar to the folded Appalachian Mountains of the eastern United States. The Sierra Madre Oriental Range veers westward west of Monterrey, forming an anticlinorium, a spectacular series of folded ridges and valleys. The mountains become more fragmented and eroded north and east of the city. ------------------------------------------------------------------------------------------- PopocatepetlorPopo Popocatépetl, or Popo, the active volcano located about 70 km southeast of Mexico City, sends a plume south on January 23, 2001. The astronaut crew on the International Space Station Alpha observed and recorded this image as they orbited to the northeast of the volcano. Popo has been frequently active for six years. On this day, the eruption plume reportedly rose to more than 9 km above sea level [for reference, Popo’s summit elevation is 5426 m (17,800 feet)]. Note the smaller ash plume below the main plume (arrow). The perspective from the ISS allowed the astronauts this unique 3 dimensional view. Popo is situated between two large population centers: Mexico City (more than 18 million people, and just off the image to the right) and Puebla (about 1.2 million people). The region’s dense population provides the potential for extreme impacts from volcanic hazards. Recent eruptions have been frequent, and have resulted in evacuations around the mountain. --------------------------------------------------------------------------------------- InternalWaves STS068-260-031 Internal Waves, Baja Peninsula, Mexico October 1994 In the sun-glint, bands of internal waves can be seen approaching the Baja Peninsula near Point Prieta in Mexico in this north-looking low-oblique view. The area of the band of internal waves is just to the north of the Bay of Sebastian Vizcaino. Internal Waves are located just below the sea surface from near 10 feet (3 meters) to over 300 feet (92 meters). They are most obvious at a density interface within the ocean, such as, the base of the upper mixed layer of thermocline. The spacing of these internal waves can vary from over 1 mile (1.6 km) to 5 miles (8 km) and they usually occur in packs of four to eight waves per packet. Oceanographers became aware of internal waves in 1975 when they were photographed in the Andaman Sea by astronauts on the Apollo-Soyuz Mission. ---------------------------------------------------------------------------------------- LakeOuiachic STS068-273-056 Lake Ouiachic, Mexico October 1994 Located in the foothills of the Sierra Madre Occidental, Lake Ouiachic (also referred to as the Lever Obregon Reservoir) can be seen in this south-southwest looking view. Lake Ouiachic is fed by and drained by the Yaqui River. The dam was completed in 1952 with the purpose to regulate water flow of the Yaqui River, prevent floods, and generate electricity. Lake Ouiachic is also an expanding tourist and resort area specializing in fishing, boating, and water skiing. --------------------------------------------------------------------------------------- ClevelandNational STS073-744-057 Cleveland National Forest, Southern California, U.S.A. October 1995 This photograph presents several manmade features—highly reflective, east-west-oriented Interstate Highway 8, near the center of the photograph, which connects the Imperial Valley of southern California with San Diego; the east-west-oriented linear feature south of Interstate Highway 8, which is part of the U.S.-Mexico border; the black Y-shaped reservoir south of Interstate Highway 8 near the 90-degree curve; and part of Mexican Highway 2 south of the border. The darker area with a hint of red (vegetation is recorded as shades of red on color infrared film) shows some of the forested, rugged mountain terrain. Several dark, faulted valleys are discernible. -------------------------------------------------------------------------------------- Thiscolorinfrared This color infrared, near-vertical photograph of Laguna de TŽrminos shows a sediment-laden lagoon that is partially bordered on one side by Carmen Island. The dynamics of the surface currents within the lagoon are revealed by the turbidity patterns in the water. Cuidad del Carmen, with a population of approximately 50 000 on the western tip of Carmen Island, has excellent port facilities that handle approximately 20 percent of Mexico's total petroleum exports. Apparently bridges on either end of the island connect the island with the mainland. The lagoon, recognized as a critical wetland area, is listed among the highest ranked habitats in Mexico for its ability to sustain a variety of plants and animals. Several small, short-flowing rivers enter the lagoon from the mainland along the south side of the lagoon. As industry develops along the southern shore of the lagoon, ecologists and environmentalists will monitor discharges into this environmentally sensitive area. The Bay of Campeche, a southern extension of the Gulf of Mexico, is the water body along the northern coast of Carmen Island. --------------------------------------------------------------------------------------- Tampico NM23-743-083 Tampico, Mexico Winter/Spring 1997 One of the leading seaports in Mexico, the city of Tampico is visible (near the center of the image) in this west-southwest-looking view. Situated on the Gulf Coastal Plain on the Panuco River 5 miles (8 km) from its mouth, Tampico boasts a port with excellent loading facilities and good communications, making it the most modern port in Mexico. Tampico has the largest fishing industries in Mexico, plus oil refineries, boatyards, sawmills, and agricultural crop and livestock facilities. The Panuco River is dredged to keep the harbor facilities open to the Gulf of Mexico (lower portion of image). The city is surrounded inland by swamps and numerous shallow lakes. Tourism is a major industry in Tampico as there are many fine beaches both to the north and south of the city. Oil refineries within the city process over a third of Mexico’s oil. Occasionally, Tampico does experience severe hurricanes from the Gulf of Mexico. -------------------------------------------------------------------------------------- Cozumel STS077-704-012 Cozumel, Mexico May 1996 The partly cloudy east coast of the Yucatán Peninsula and the resort island of Cozumel are apparent in this southwest-looking, low-oblique photograph. Cozumel Island, a popular tourist and resort area 24 miles (39 kilometers) long and 7 miles (11 kilometers) wide, is noted for its beautiful beaches and spectacular coral reefs. Point Molas is visible at the northeast tip of the island. Expansion of roads and clearings for homes, golf courses, and other recreational features are discernible. Cozumel and the Yucatán Peninsula are susceptible to hurricanes from July through mid-October. Hurricane Gilbert in 1987 was the last major hurricane to hit the area. ---------------------------------------------------------------------------------------- OpenPit STS078-735-20 Open Pit (Copper) Mine, Sonora, Mexico June 1996 The rugged, mountainous terrain of the Sierra Madre Occidental is evident in this near-nadir image of a section of northeastern Sonora State. The only three identifiable features are a reservoir, a river valley, and a large open pit-mining site. The Angostura Reservoir (opaque, elongated feature near the northern side of the image) is located in the river valley (north-south orientation) that is a tributary of the Yaqui River system. The highly reflective areas in the center of the picture is the “La Cardidad” open pit mine, that is located east of the small town of Nacozari (not identifiable on this small scale image). This mining site is one of the largest copper and molybdenum operations in the northwest Mexico. --------------------------------------------------------------------------------- MexicoFall NM22-741-54B Mexico City, Mexico Fall/Winter 1996 One of the world’s largest metropolitan areas, Mexico City, is located near the center of the picture. Although the urban infrastructure of the city is barely discernible on this small scale image (Lake Texcoco, the large, dark rectangular feature and several major thoroughfares) the image does show the vegetated slopes (darker areas) of the numerous volcanoes that almost encircle Mexico City. A semi-circle of clouds is visible over the volcanic mountains east and south of the rapidly expanding urban area. Several isolated, large composite volcanoes and numerous smaller cinder cones are scattered throughout this arid region of the Mexican Plateau. ---------------------------------------------------------------------------------------------- SmokeIsthmus STS091-713-024 Smoke, Isthmus of Tehuantepec June 1998 The north coast of the Isthmus of Tehuantepec is visible through the veil of smoke that was caused by burning brush to clear land for agriculture in southern Mexico. Identifiable features include the city of Villahermosa (cluster of reflective surface area near the middle right edge of image); several river channels that flow across this low lying swampy coastal plain; and Point Frontera, which is the pointed-looking delta that juts northward into the Bay of Campeche (Refer to STS91-701-074 for another picture of smoke/fires that are burning along the south coast of the Isthmus of Tehuantepec). --------------------------------------------------------------------------------------- SierraMadre NASA6-712-052 Sierra Madre del Sur, Acapulco, Mexico Fall/Winter 1997 The rugged mountains of the Sierra Madre del Sur (bottom portion of image) and the vacation resort city of Acapulco (near the center of the image) are discernible in this south-looking view. The Sierra Madre del Sur or as it is sometimes referred to, the Southern Highlands, are made up of ancient crystalline rock that has been dissected into deep V-shaped valleys creating a landscape of steep slopes and knife-edged ridges. Acapulco and its excellent harbor, is fairly isolated by the rugged ranges of the Sierra Madre del Sur to its north. The city is a shipping point for the agricultural products of the region and has suffered frequent earthquakes and hurricanes. A major hurricane during the late summer of 1997 brought above normal amounts of precipitation to the mountains of the Sierra Madre del Sur and the coastal regions surrounding the city of Acapulco. Flooded streams brought water, mud, and debris down the mountain slopes into the city, destroying many homes and other buildings. Many people were killed or injured and many more were made homeless. --------------------------------------------------------------------------------- Aguascalientes STS080-702-094 Aguascalientes Area, Mexico November 1996 Aguascalientes, the highly reflective area near the center of the image, is the capital of the state with the same name. Located approximately 110 miles (175 km) northeast of Guadalajara, this urban area located on the Mexican Plateau (6486 feet - 1977 meters above sea level) was named for the numerous thermal springs that are found in the area. This region of the semi-arid Mexican Plateau is characterized by rugged mountains (darker features west of the city) separated by basins. Some of the elevated landscape (slightly darker features) display evidence of recent volcanic activity. The meandering channel of the Rio Verde Grande de Balem (aligned north-south) can be seen as it passes along the west side of Aguascalientes. The Presidente Calles Reservoir is barely visible (shaped like letter E) north, northwest of the city. --------------------------------------------------------------------------------------- SanLuisPotosi STS080-702-095 San Luis Potosi, Mexico November 1996 The concentration of highly reflective surfaces (near the center of the image) is the city of San Luis Potosi. In addition to being located on the arid to semi-arid Mexican Plateau that averages 6500 feet - 1980 meters above sea level, San Luis Potosi is flanked by several mountain ranges (darker, eroded features), particularly west, south, and even east of the developing urban area. San Luis Potosi is favorably located to function as an important ground transportation hub for central Mexico (the thin, light colored lines appear to be recently constructed highways). For example consider that the so-called NAFTA (North American Free Trade Agreement) Highway, basically a north-south artery, passes through the city. There is also an east-west highway linkage that connects the Gulf of Mexico coast with the west coast of Mexico that also passes through the city. San Luis Potosi is an important stop for one of Mexico’s principal railroad lines (railroad right of way is very difficult to trace across the computer image). -------------------------------------------------------------------------------------- BajaCalifornia STS080-706-008 Baja California, Mexico November 1996 Several large areas of volcanic activity, forming plateau-like features, are easily identified along the west coast of Baja California. The geologic structure in the center of the image is an old, severely eroded volcano, which is the southernmost feature of the Sierra Viscaino (also known as the Sierra Santa Clara). The center of the eroded caldera is visible almost exactly in the middle of the picture. More resistant large lava-formed lobes can be seen immediately south of the old caldera. The dark feature southeast of the volcano (upper left corner) is the northern end of Laguna San Ignacio, while the dark feature in the upper right corner of the image is Bahia San Hipolito. The light colored lines traversing this arid environment are roads that connect the coastal areas with the main highway that extends northwest to southeast throughout the Baja California peninsula. -------------------------------------------------------------------------------------- LagunaSanIgnacio STS081-724-022 Laguna San Ignacio, Baja California, Mexico January 1997 The dark, finger-like protrusion of the Pacific Ocean that extends into the southwest coast of Baja California is called Laguna San Ignacio. Laguna San Ignacio is one of several breeding lagoons that gray whales use along the west coast of Baja California. Smaller estuaries (dark features) that parallel the coast are also visible. The flat, highly reflective terrain immediately west of the large lagoon has been converted into an area where salt ponds have been established for the commercial production of salt. Seawater is pumped through a series of gravity fed ponds thereby increasing the salt content through a natural evaporation process. The deeply eroded plateau structures northwest and especially southeast of the Laguna San Ignacio are part of a series of volcanic erosional surfaces that have formed along the west coast of Baja California. The single, narrow, light colored line is a road that connects the coastal area with the other parts of Baja California. -------------------------------------------------------------------------------------------- Magdalena STS081-724-024 Magdalena Bay, Santa Margarita Island, Mexico January 1997 Magdalena Bay, an inlet of the Pacific Ocean, can be seen in this south-looking view. Located on the Pacific Ocean in southwestern Baja California, the rather narrow Magdalena Bay is the winter home to some of the largest animals on Earth. At the end of their 5000 mile (5650 km) journey from the Bering Sea between Russia and Alaska, thousands of gray whales congregate each year in the protected bay waters to mate, bear their young, and pass the winter months before returning to the Bering Sea in the Spring. The bay is also home to sea lions, dolphins, and other types of large whales. Magdalena Bay is located in a semi-arid wilderness surrounded by rugged islands, uninhabited beaches, sand dunes, and mangrove channels. Thousands of tourists visit this region each winter to observe the large numbers of animals congregating in and around the bay. Near the left center of the image, the small, but rugged island of Santa Margarita can be seen. --------------------------------------------------------------------------------------- SierraMadreOriental STS087-706-5 Sierra Madre Oriental, Mexico November 1997 The folded, rugged, Sierra Madre Oriental (eastern), a southern extension of the Rocky Mountains of the United States and Canada, can be seen in this west-northwest view. The Sierra Madre Oriental is the boundary of the dissected eastern edge of the High Mexican Central Plateau and the Gulf coastal plain. Beginning as barren hills south of the Rio Grande in northeastern Mexico, the Sierra Madre Oriental extend generally southward approximately 700 miles (1125 km), to near 19 degrees north latitude paralleling the coast of the western Gulf of Mexico. The average elevation of the mountain range is 7000 feet (2135 meters) with some peaks exceeding 10000 feet (3050 meters). A wealth of minerals including iron ore, lead, silver, and gold, are extracted from the mountain range. The city of Monterey, Mexico is discernible just inward toward the center from the left center of the image. Clouds cover the coastal plain in the bottom third of the image. --------------------------------------------------------------------------------------- Acapulco STS090-732-076 Acapulco, Mexico April 1998 Near the center of the image, the international resort city of Acapulco and Acapulco Bay can be seen in this north-northeast-looking view. With the city’s fine natural harbor, considered one of the best in Central America, Acapulco is a shipping point for the agricultural products of the region including cotton, fruit, and tobacco. The Bay of Acapulco is surrounded by cliffs and promontories and served as a base for the Colonial Spanish exploration of the Pacific. The port also served as the chief port for Spanish trade with the Philippines from 1565 to 1815. To the left or west of Acapulco, the Coyuca Lagoon is visible. Near the top left of the photo, smoke is visible from fires burning in the foothills of the Sierra Madre del Sur. To the right or southeast of Acapulco, the Tres Palos Lagoon is visible. On the corridor of land separating the Tres Palos Lagoon from the Pacific Ocean, the runways of the General Juan N. Alvarez International Airport are discernible. Acapulco has suffered frequent earthquake and hurricane damage. A hurricane in the late summer of 1997 caused severe flood damage to the city and the surrounding area due to excessive rains spawned by the storm. ---------------------------------------------------------------------------------------- MazatlanSinaloa STS090-740-069 Mazatlan, Sinaloa, Mexico April 1998 The physical setting of the popular resort city of Mazatlan (concentration of light colored area along the coast near the center of the picture), with an estimated 500,000 in population, is visible along this section of the west coast of Mexico. Immediately inland from the extensive coastal beaches, two lagoons that parallel the coastline can be identified southeast of Mazatlan. The general topography along the narrow coastal plains consist of rolling, vegetated hills (darker terrain) and drier, less vegetated valleys (lighter colored landscape). The general climate for this area along the west coast of Mexico is semi-arid. --------------------------------------------------------------------------------------- Veracruz STS094-731-017 Veracruz, Mexico July 1997 Located on the Gulf of Mexico, the city of Veracruz can be seen in this north-northeast-looking view. Veracruz stands on a low sandy plain surrounded by dunes and swamps, some of which have been reclaimed and are very fertile. Rivaling its northern neighbor Tampico as Mexico’s main port, Veracruz is the commercial and industrial center of an important oil region, as well as a major tourist resort with beautiful scenery, fine beaches, and excellent accommodations. Besides oil refineries, Veracruz’s industries include cigars, chocolate, liquors, tiles, and footwear. Lake Mandinga Grande is visible to the south (right) of the city. Scattered small islands and coral reefs are visible in the Gulf of Mexico to the east and southeast of the city. Scattered clouds cover the foothills of the Sierra Madre Oriental in the bottom left portion of the image. ------------------------------------------------------------------------------------ FiresIsthmus STS091-701-074 Fires, Isthmus of Thuantepec, Mexico June 1998 Many of the extensive, land clearing fires and the resultant smoke on the forested slopes of the mountains in southern Mexico are seen in this southwest-looking view of the Isthumus of Tehuantepec. The two major features that help to identify the specific geographic area in this image are the dark, crescent-shaped feature with the irregular edges (Nezahualcayotl Reservoir—left center of image) and the dark Muerto Lagoon and the Gulf of Tehuantepec (upper right corner). The environmental impact of these fires at times reached as far north as the central plains of the United States. (Refer to STS91-713-024 for fires and smoke palls along the Bay of Campeche coast of Mexico). ----------------------------------------------------------------------------------------------- PopocatepetlandIztaccíhuatl Popocatepetl and Iztaccíhuatl Volcanoes, Mexico As part of the circum-Pacific “Ring of Fire,” Mexico hosts several of the world’s most continually active volcanoes, including the massive Popocatepetl (Aztec for “smoking mountain.”) This detailed, oblique astronaut photograph also depicts a neighboring volcano, Iztaccíhuatl (the “Woman in White.”) With North to the right in the scene, the view is a westward-looking perspective. The faint plume emanating from Popocatepetl’s 250- to 450-meter-deep summit crater attests to the significant, ever-present hazard the volcano represents to the 25 million people living in the region, including the nearby city of Amecameca, as well as the metropolitan centers of Mexico City to the northwest and Puebla to the east. Popocatepetl has produced small, intermittent eruptions since 1994. In addition to the constant danger of eruptions producing ash deposits, pyroclastic flows, and lava (see an earlier astronaut photograph of Popocatepetl erupting), the summit of Popocatepetl also hosts glaciers. These can melt during eruptions to form dangerous mudflows that blanket areas to the south. In contrast to Popocatepetl’s well-defined symmetrical cone, Iztaccíhuatl is formed from several overlapping smaller cones that trend north-northwest to south-southeast. Glaciers and year-round snow are also present on Iztaccíhuatl (white regions along the peaks). Deep valleys have been eroded into the massive apron of ash and pumice deposits, glacial outwash, and alluvium to the east of the volcano. Despite its close proximity, similar age, and similar geologic character to Popocatepetl, Iztaccíhuatl has not erupted in historic times. This has encouraged the establishment of numerous agricultural fields (visible as faint rectilinear patterns in the lower half of the image) on the eastern flank of the mountain. -------------------------------------------------------------------------------------------------