Where on Earth...? |
This natural-color mystery image from NASA's Multi-angle Imaging SpectroRadiometer (MISR) covers an area of about 374 kilometers x 276 kilometers and was acquired in mid-February, 2005. This mystery concerns the geography and weather of the region.
A major river enters at the the left-hand image margin and runs across the image area. Two other large rivers also enter from the left-hand edge, one from the the south, and one from the north. These three rivers converge near a regional capital city, apparent as the large area of pale gray pixels near the junction of these three rivers. Name that capital city and these three rivers.
Answer: The image area encompasses the eastern Ganges plain and the States of Bihar and Jharkhand. In the top part of this image, Bihar is bisected by the Ganges River (which is also popularly known by its Hindu name, Ganga). The Son River (also spelled Sone River) joins the Ganges from the south, and the Gandak River joins from the north. A very small portion of the Gaghra River is also apparent here, as it joins with the Ganges just upstream from its confluence with the Sone. Patna, the capital city of Bihar, is located downstream from the Sone and opposite the confluence of the Ganges and the Gandak. The smaller river of Punpun only becomes navigable during the rains.
The following four statements concern the art and prehistory from a particular jurisdictional region (in this case, a state) of which the aforementioned city is the capital. Three of the statements are true. Which statement is false?
Answer: A is false.
Patna became a great city by about 300 BC (Patna was previously called
Pataliputra). In its long history, the surrounding region has seen the rise and
fall of several kingdoms and empires. There are more than twenty archaeological
sites within Bihar, and there are at least three stone-age archaeological
sites, including several Neolithic settlements such as the one at Chirand
(which is situated about 50 kilometers from Patna). The state-owned Patna
Museum boasts a large number of pre- and proto-historic objects of relevance to
Indian art and history. An important painting style from Bihar is the art of
the Madhubani, which is traditionally passed from mothers to their daughters.
Along the banks of the major river that traverses the image, some dust has been swept aloft by strong winds. During this season, is the east-west component of the surface winds typically from the west, or do such winds generally blow from the east?
Answer: Either "neither" or "west" accepted.
For the eastern Ganges plain, the prevailing surface winds for the December -
February season are northerly, light and variable. Recent measurements
indicate that the prevailing winds at 850 millibars (850 mb is within the
lower levels of the atmosphere) are northwesterly. A number of older records
also indicate that the winter monsoon of the eastern Ganges plain is from the
northwest, although the prevailing wind direction cannot be conclusively
established from those records. Therefore, either "west" or
"neither" (no east-west component) are acceptable answers.
Another major river enters at the upper image margin, and curves downward to converge with the major river that runs across the entire image. Three of the following four statements about the area surrounding the curved river are true. Which statement is false?
Answer: C is false.
The Kosi River in north Bihar is notorious for the meandering behavior of its
east-to-west course. In the past 250 years, the Kosi has moved westwards by
more than 100 kilometers. During the summer floods, the Kosi has been known to
attain a width of over 30 km on the nearly flat Ganges plain. In 1955, the
river was harnessed with the construction of a barrage. Since then, a series of
canals, levees and embankments have channeled the river, providing plenty of
irrigation water for north-east Bihar. Although the embankments have calmed the
Kosi, flow regulation can not be said to have reduced the severity and duration
of flooding, and embankment breaches have occurred in many years including
1968, 1984, 1987, 1988, 2001, 2002, 2003 and 2004. The breaches are partly due
to the extremely high silt content of the Kosi waters, which cause erratic and
unpredictable morphological changes and bank erosion. As the embankments become
choked with silt, seepage occurs and forces the bed level and the water table
to rise. The embankments have been raised over 2 meters since their original
construction in order to keep pace with the rising river bed. Some amount of
previously arable countryside have been devastated by this rise in the water
table, and it is reported that during the wet monsoon season, the only dry
place for some villagers living at the southern tip of the West Kosi embankment
is atop the embankment itself. Although now extremely rare, the Ganges River
dolphin, Platanista gangetica, is still found within the Kosi River.
The tan and orange hues in the lower portion of the image area are associated with a plateau region in which many minerals have been mined. Three of the following four statements about mining in the region are true. Which one is false?
Answer: B is false (C also accepted as false).
Through bifurcation of Bihar in November 2000, the new Indian state of
Jharkhand was formed. Jharkhand is comprised of about 45% of the geographical
area of undivided Bihar. The southern portion of Bihar became Jharkhand, which
now includes most of the Chhotanagpur plateau, to which many of the mineral
resources of the region are bestowed. Northeastern India does not possess
significant quantities of lateric nickel, molybdenum or tin. However, Bihar
(before division) produced much of India's copper, and both gold (south of
Chhotanagpur) and uranium (at Jadugudda in southern Jharkhand) are found today
in Jharkhand. The southern Chhotanagpur plateau region was the single most
important source for iron ore, coal, and bauxite within India, and undivided
Bihar produced about 45% of India's iron ore. Iron was also extremely important
for India's ancient history, since the increasing adoption of iron implements
made it possible to remove dense forest and plough heavy clay soils, but rich
iron ore deposits were only found within southern Bihar and Orissa. Ancient
cities in Bihar (such as Rajgir) are testimony to these developments. The iron
ore deposits of southern Bihar and Orissa were the only reliable sources of
iron ore during India's ancient history. Since the iron ore deposits at Orissa
are situated a few hundred kilometers to the south of this image, C is also
accepted as a false statement.
MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.
Image credit: NASA/GSFC/LaRC/JPL, MISR Team.
Text acknowledgment: Clare Averill (Raytheon ITSS/ Jet Propulsion Laboratory).