August 2nd, 2010 Category: Image of the day, Lakes, Rivers

USA - June 20th, 2010

Despite the arid desert stretching across most of this image of the western United States and northwestern Mexico, quite a few areas of agriculture can be observed. The most evident are those of the Great Central Valley in California, on the left hand side of the image.

Upon opening the full image, more agriculture, created by irrigation schemes, can be seen near the Salton Sea, a lake visible at the bottom center, and at the top center of the image. These fields appear mostly rounded, with varying shades of green.

Another important body of water visible here is Lake Mead, on the Colorado River. The lake is situated just to the right of the image center, and can be quickly found thanks to its three-armed shape.

Tags: Agriculture California Great Central Valley Lake Mead Salton Sea |  Print This Post |  Email This Post | | Leave a comment

April 30th, 2010 Category: Rivers

Russia - February 18th, 2010

Rostov Oblast is a federal subject of Russia (an oblast), located in the Southern Federal District. Rostov Oblast lies in the south of the country with an area of 100,800 km² and a population of 4,404,013 (2002 Census) making it the fifth most populous federal subject in Russia.

Its administrative center is the city of Rostov-on-Don (center left edge), which also became the administrative center of the Southern Federal District in 2002. The city is located on the banks of the Don River, one of Europe’s largest. In this orthorectified image, the river can be seen flowing across the oblast. Many fields are visible north and south of the river.

Tags: Agriculture ASAR Asia Don River Orthorectification Rostov Oblast Rostov-on-Don Russia Southern Federal District |  Print This Post |  Email This Post | | Leave a comment

April 19th, 2010 Category: Image of the day, Rivers

Sudan - March 5th, 2010

Sun glint causes the White Nile River to appear truly white as it flows past the fields of the Gezira Scheme in Sudan. The Blue Nile borders this agricultural area to the east. The two rivers converge at Khartoum, near the top of the image.

The Gezira Scheme is one of the largest irrigation projects in the world, now covering about now covers 3,400 miles² (8,800 km²) in the Sudanese state of Al Jazirah. It is composed of thousands of kilometers of canals that distribute water from the Blue Nile to farms between the two rivers.

The Gezira (which means “island”) is particularly suited to irrigation because the soil slopes away from the Blue Nile and water therefore naturally runs through the irrigation canals by gravity . The soil has a high clay content which keeps down losses from seepage. The main crop grown in this region is still cotton.

Tags: Africa Agriculture Al Jazirah Blue Nile River Gezira Scheme Irrigation Khartoum Sudan White Nile River |  Print This Post |  Email This Post | | Leave a comment

April 2nd, 2010 Category: Lakes, Rivers

Egypt - March 5th, 2010

The Nile River flows out of Lake Nasser, created by the Aswan High Dam, in Egypt, on its way northward to the Mediterranean Sea. The lake is some 550 km long and 35 km across at its widest point. It covers a total surface area of 5,250 km² in Egypt and Sudan and has a storage capacity of some 157 km³ of water.

of the reservoir are the Toshka Lakes, created by water drained from Lake Nasser in order to control its water level. This water is also used to irrigate crops in the region – here, some circular fields can be seen between Lake Nasser and the Toshka Lake located furthest eastward.

Tags: Africa Agriculture Aswan High Dam Circular Crops Egypt Lake Nasser Nile River Toshka Lakes |  Print This Post |  Email This Post | | Leave a comment

February 14th, 2010 Category: Image of the day, Lakes, Rivers

Egypt - January 3rd, 2010

The thick green band running vertically through the center of this image is fertile land along the banks of the Nile River, in Egypt. Upon opening the full image, the Nile itself can be seen as a thinner, dark blue ribbon towards the right edge of the green land.

Branching off to the west is a heart-shaped area of green land known as the Faiyum Oasis. It is a depression or basin in the desert immediately to the west of the Nile south of Cairo. The extent of the basin area is estimated at between 490 mi² (1,270 km²) and 656 mi² (1700 km²). Over 400 mile² (1,000 km²) of the Faiyum Oasis is cultivated, the chief crops being cereals and cotton.

The basin floor comprises fields watered by a channel of the Nile, the Bahr Yussef, as it drains into a desert depression to the west of the Nile Valley. The Bahr Yussef veers west through a narrow neck of land north of Ihnasya; it then branches out, providing rich agricultural land in the Faiyum basin, draining into the large saltwater Lake Moeris (Birket Qarun), visible as a blue area at the upper limits of the green land.

Differing from typical oases, whose fertility depends on water obtained from springs, the cultivated land in the Faiyum is formed of Nile mud brought down by the Bahr Yussef, 15 miles (24 km) in length. Between the beginning of Bahr Yussef at El-Lahun to its end at the city of Faiyum, several canals branch off to irrigate the Faiyum Governorate. The drainage water flows into Lake Moeris.

Tags: Africa Agriculture Bahr Yussef Birket Qarun Egypt Faiyum Faiyum Oasis Ihnasya Lake Moeris Nile River Nile Valley |  Print This Post |  Email This Post | | Leave a comment

February 11th, 2010 Category: Image of the day, Rivers

Sudan - January 26th, 2010

The Nile River, generally regarded as the longest river in the world, can be seen making its way through Egypt (above) and Sudan (below) in this image of northern Africa. Here, the stretch of the river from Lake Nasser (above) to the confluence of its two major tributaries, the White Nile and Blue Nile, near Khartoum (below).

Upon opening the full image, two other segments of the great river can be observed. The first is a part of the river north of Lake Nasser, surrounded by fertile green land. The second is south of Khartoum, and includes the agricultural land of the Gezira Scheme.

Tags: Africa Agriculture Blue Nile Egypt Gezira Scheme Khartoum Lake Nasser Nile River Sudan White Nile |  Print This Post |  Email This Post | | Leave a comment

February 5th, 2010 Category: Snapshots

Paraguay - January 25th, 2010

The Gran Chaco is a sparsely populated, hot and semi-arid lowland region of the Río de la Plata basin, divided between eastern Bolivia, Paraguay, northern Argentina and a portion of the Brazilian states of Mato Grosso and Mato Grosso do Sul, where it is connected with the Pantanal region. This land is sometimes called the Chaco Plain.

Historically the Chaco has been divided in three main parts: the Chaco Austral or Southern Chaco, inside Argentinian territory; the Chaco Central or Central Chaco, also now in Argentinian territory; and the Chaco Boreal or Northern Chaco, inside Paraguayan territory and sharing some area with Bolivia.

This image focuses on the Chaco Boreal in Paraguay. The area in the center appears tan due to agricultural fields, many of which are near mennonite colonies. Inside Paraguay, people sometimes use the expression Central Chaco to refer to this area, located roughly in the middle of the Chaco Boreal, where such mennonite colonies are established.

The Chaco offers high soil fertility and a topography that is favorable for agricultural development, but in combination with aspects that are challenging for farming: a semi-arid to semi-humid climate (600–1300 mm annual rainfall) with a six-month dry season and sufficient fresh groundwater available only in roughly one third of the region, the remainig aquifers been too salty.

Tags: Agriculture Central Chaco Chaco Boreal Filadelfia Gran Chaco Northern Chaco Paraguay Río de la Plata Basin South America |  Print This Post |  Email This Post | | Leave a comment

January 21st, 2010 Category: Image of the day

Libya - December 16th, 2009

The Messak Sattafat plateau rises above the sand dunes of the Sahara Desert in Fezzan, a south-western region of modern Libya. Fezzan is thus divided into two sub-basins by the Messak Sattafat, a Nubian Sandstone escarpment and associated dip-slope plateau.

The region as a whole is largely desert but broken by mountains, uplands, and dry river valleys (wadis), where oases enable ancient towns and villages to survive deep in the otherwise inhospitable Sahara. Upon opening the full image, two agricultural areas of circular irrigated fields can be observed in the upper half of the image, both north and south of the Messak Sattafat plateau.

Tags: Africa Agriculture Fezzan Libya Messak Sattafat Sahara Desert Sand Dunes |  Print This Post |  Email This Post | | Leave a comment

January 7th, 2010 Category: Rivers

USA - November 8th, 2009

The Mississippi River (right) forms most of Arkansas’s eastern border, except in Clay and Greene counties and in dozens of places where the current channel of the Mississippi has meandered from where it had last been legally specified.

Arkansas is a land of mountains and valleys, thick forests and fertile plains. The so-called Lowlands are better known by names of their two regions, the Delta and the Grand Prairie. The Arkansas Delta is a flat landscape of rich alluvial soils formed by repeated flooding of the adjacent Mississippi. Further away from the river, in the southeast portion of the state, the Grand Prairie consists of a more undulating landscape. Both are fertile agricultural areas.

Tags: Agriculture Arkansas Arkansas Delta Grand Prairie Mississippi River |  Print This Post |  Email This Post | | Leave a comment