Earth Snapshot RSS Feed Twitter
 
 
 
 

Posts tagged Laguna Madre

Environmental Issues Facing the Laguna Madre, Mexico and USA

25.5N 97.7W

February 28th, 2013 Category: Climate Change, Lakes

Mexico – January 26th, 2013

Visible south of the bend in the coastline is the Laguna Madre, located on a coastal plain of the Gulf of Mexico. It is the largest hyper-saline coastal wetland in North America and one of seven in the whole world. It harbours a wealth and diversity of species and ecosystems, due to the fact that the lagoon is located between two biogeographical regions, the Nearctic and the Neotropical regions, with the influence of the Carolinian and the Caribbean marine provinces giving rise to various types of soil, climate and rainfall regimes and relative humidity.

The most important human impacts on this region over the past 30 years have been: water diversion and flood-control projects, brushland clearing, pollution, continued dredging, and pressures from population growth. The lower Laguna Madre, for instance, has lost about 60 square miles of seagrass cover due to reduced water clarity since the 1960s. Extensive agriculture has fragmented and reduced the areas of native terrestrial ecosystems. In addition, the large number of people now living in “colonias” without sewage treatment contributes to the contamination of ground and surface waters and poses a human health problem. This is worsened by untreated wastewater from Mexican municipalities released into the Rio Grande.

Global warming will compound these human pressures on Laguna Madre, in some cases improving, in others cases worsening the situation. For example, if future climate change brings a prolonged and more intense wet season in this region, the reliability of rainfall and soil moisture could improve. In wet periods, the land can retain rainfall and runoff, so wildlife and native plants increase their productivity, and the lagoon’s salinity is moderated.

If rainfall decreases in the future, however, a relatively small reduction in moisture could lead to increased desertification. Moreover, all types of coastal wetlands in Texas would decline with less freshwater delivery to the estuaries, thus worsening wetland losses already occurring. Over the long term, such coastal wetland losses would diminish estuarine-dependent fisheries.

Warmer winters are especially important from an ecological point of view. A northward shift of the freeze line would bring dramatic effects to the Coastal Bend and upper Laguna Madre, allowing southerly plant and animal communities to expand northward and, due to fewer disturbances from frost, mature and develop different ecosystems over time (click here for more information).

Bays Along Texas Coastal Bend by Gulf of Mexico – January 25th, 2012

27.8N 97.3W

January 25th, 2012 Category: Image of the day

USA - January 5th, 2012

This wide-swath ASAR image shows bays along the Texas Coastal Bend, the flat area of land along the Texas coast.  The Coastal Bend includes the barrier islands of Texas and the Laguna Madre (visible in the lower part of the full image). The bays visible here (from northeast to southwest) are: San Antonio Bay, Aransas Bay, Corpus Christi Bay and Baffin Bay.

San Antonio Bay is a bay on the Texas Gulf coast situated between Matagorda and Aransas Bay. It consists mainly of the combined waters of the San Antonio and Guadalupe rivers, and is located at the mouth of the Guadalupe River, about 55 miles (89 km) northeast of Corpus Christi and 130 miles (209 km) southeast of San Antonio. It is protected from the Gulf of Mexico by Matagorda Island, leaving only relatively small and distant outlets to the Gulf for little mixing of bay and Gulf waters. The remoteness of the bay has prevented the establishment of major ports.

Aransas Bay is a bay on the Texas gulf coast, approximately 30 miles (48 km) northeast of Corpus Christi, and 173 miles (278 km) south of San Antonio. It is separated from the Gulf of Mexico by San José Island (also referred to as St. Joseph Island). Aransas Pass is the most direct navigable outlet into the Gulf of Mexico from the bay. The bay is oriented laterally northeast-southwest, and is extended by Redfish Bay to the southwest, Copano Bay to the west, Saint Charles Bay to the north, and Mesquite Bay to the northeast.

Corpus Christi Bay is a scenic semi-tropical bay on the Texas coast found in San Patricio and Nueces counties, next to the major city of Corpus Christi. It is separated from the Gulf of Mexico by Mustang Island, and is fed by the Nueces River and Oso Creek from its western and southern extensions, Nueces Bay and Oso Bay. The bay is located approximately 136 mi south of San Antonio, and 179 mi southwest of Houston.

Baffin Bay is a bay in South Texas, an inlet of the larger Laguna Madre. The Laguna Madre is a long shallow hypersaline bay along the western coast of the Gulf of Mexico in Nueces, Kenedy, Kleberg, Willacy and Cameron counties in Texas, United States. It is separated by the roughly 20-mile (32 km) long Saltillo Flats land bridge into Upper and Lower bays. The two are joined by the Intracoastal Waterway, which has been dredged through the bay. Cumulatively, Laguna Madre is approximately 130 miles (209 km) long, the length of Padre Island. The main extensions include, Baffin Bay in Upper Laguna Madre, Red Fish Bay just below the Saltillo Flats and South Bay (Texas) near the Mexican border.

Laguna Madre and Cities of Saltillo and Monterrey, USA and Mexico – January 11th, 2012

25.6N 100.3W

January 11th, 2012 Category: Image of the day, Lakes, Mountains

Mexico and USA - January 10th, 2012

The flat, coastal plains near the Texas-Mexico border contrast with the mountain ranges in Mexico visible further inland. Two large cities can be observed by these mountain ridges: Saltillo (closer to left edge) and Monterrey (slightly northeast of the former).

Visible by the coast are two large lagoons. The thin, green one at the top right is the Laguna Madre, a long shallow hypersaline bay along the western coast of the Gulf of Mexico in Texas, USA. It is separated by the roughly 20-mile (32 km) long Saltillo Flats land bridge into Upper and Lower bays. Cumulatively, Laguna Madre is approximately 130 miles (209 km) long, the length of Padre Island. The main extensions include, Baffin Bay in Upper Laguna Madre, Red Fish Bay just below the Saltillo Flats and South Bay (Texas) near the Mexican border.

Laguna Madre near Gulf Coast, Mexico

25.0N 97.6W

August 18th, 2011 Category: Lakes

Mexico - July 31st, 2011

Near the top of this image is the border between Texas, USA (above) and Mexico (below). Parallel to the coast is the Laguna Madre, separated from the Gulf of Mexico on the east by a number of barrier islands, including Barra Los Americanos, Barra Jesús María, and Barra Soto la Marina. The lagoon is bounded on the west by mainland Tamaulipas. It is located in the municipalities of Matamoros, San Fernando, and Soto la Marina.

The Laguna Madre is very shallow, with an average depth of only 0.9 m. The lagoon is connected to the ocean by only two narrow inlets, so the tidal range – which is already minor in this part of the Gulf of Mexico – is negligible.  Atmospheric effects are much more important than tides in its circulation; its weak currents generally follow the prevailing winds, and these winds can influence the water level by as much as a meter.

Oceanographically, the Laguna Madre is considered a hypersaline lagoon; this indicates that it is usually much saltier than the ocean, due to being nearly landlocked in a semiarid environment. This is because its salinity can vary wildly depending on rainfall and freshwater inflow, from as high as 120 ppt (12%) – over three times saltier than the ocean – to as low as 2 ppt (0.2%) after a heavy rain.

Laguna Madre and Sierra Madre Oriental Range, USA and Mexico

25.1N 98.7W

September 1st, 2010 Category: Lakes, Mountains, Rivers

Mexico - August 4th, 2010

The Laguna Madre (meaning “Mother Lagoon” in Spanish), in the upper right corner, appears silvery in color due to sun glint. The lagoon is actually two long, shallow bays along the western coast of the Gulf of Mexico, in  both the USA and Mexico. The two bays are separated by the mouth of the Rio Grande.

An area of green coastal plains can be observed to the west of the lagoon. Further west lies the Sierra Madre Oriental mountain range, whose peaks appear darker brown and more marked as one moves southward. Some areas of white and tan arid terrain can be seen further to the west and to the north.

About Us

Earth Observation

Organisations

Archive

October 2019
M T W T F S S
« Mar    
 123456
78910111213
14151617181920
21222324252627
28293031  

Categories


Bulletin Board


Featured Posts

Information

41


Take Action

Widgets