“SHRINKING SNOWCAPS AND RISING TIDES – THE RESPONSE OF THE ARABIAN SEA ECOSYSTEM TO CLIMATE CHANGE”
Joaquim Goes and Annette DecharonOriginally presented 12 April 2014
This E2C focuses on the Arabian Sea, west of India and east of the Horm of Africa
http://go.hrw.com/atlas/norm_htm/indian.htm
The Indian Ocean
• Smallest, youngest, and physically most complex of the three major oceans
• Approximately 1/5th of total ocean area
• 10,000 km (6,200 mi) between Africa and Australia
• Deepest spot is the Sunda Deep in the Java Trench (7,450 m/ 24,442 ft)
• Marginal seas include the Red Sea, Persian Gulf, gulfs of Aden and Oman, Bay of Bengal, Andaman Sea, and Arabian Sea
The Arabian Sea
http://upload.wikimedia.org/wikipedia/commons/4/41/Arabian_Sea_map.png
Monsoons
• Regional weather dominated by the “monsoons”
• Seasonal reversals of wind producing “wet” and “dry” seasons
• Controls economies of Southeast Asia, parts of Africa, and even parts of the USA
• Long used by mariners to travel across the Indian Ocean
• Sailors used the winds and currents of the “Northeast” and “Southwest” monsoons in trade routes for centuries.
Summer Monsoon – “Wet Season”
• Generally Apr – Sep• Rising warm air over
inland mountains bring moist air from SW Indian Ocean
• Torrential rains, often flooding
• Vital for agriculture and hydroelectric power
http://education.nationalgeographic.com/education/encyclopedia/monsoon/?ar_a=1
Winter Monsoon – “Dry Season”
• Oct to Apr • Winds blow from
northeast, originating above Mongolia and northeastern China
• Himalayas block cool air, keeping coast warm
• Banyan trees bent by strong monsoon winds
http://education.nationalgeographic.com/education/encyclopedia/monsoon/?ar_a=1
World Ocean Currents
http://www.es.flinders.edu.au/~mattom/IntroOc/notes/figures/images/fig2a2.gif
http://www-pord.ucsd.edu/~ltalley/sio210/Indian/11circ.gif
West and East India Countercurrents
http://iri.columbia.edu/~lareef/tsunami/indianoceancurrents.gif
The Himalayas
The Other Piece of the Situation
• Youngest, highest mountains on Earth
• Stretch 2400 km/1500 mi across India, China, Pakistan, Afghanistan, Butan, and Nepal
• Three parallel ranges
The Himalayas and Monsoons
• Monsoon patterns are connected with the Himalayas
• LDEO Tree Ring Lab researchers have conducted extensive investigations in Nepal and adjacent regions
https://www.ldeo.columbia.edu/tree-ring-laboratory/tree-ring-research/nepal/the-monsoon-over-himalayas
Uplift of the Himalayas “Sparked” Monsoons in SE Asia
• Uplift began about 50 million years ago as “India” collided with “Asia”
• “Continental-continental plate boundary”
• Ocean Drilling Project (ODP) investigated the onset of monsoon patterns in the 1990s
• “From Mountains to Monsoons” CD-ROM was one of the first educational efforts
http://odplegacy.org/outreach/cdroms.html
Modern Observation Techniques--TRMM
• TRMM (Tropical Rainfall Measuring Mission) is a NASA-Japan satellite that has been of the utmost value in monitoring precipitation in 30 o N- 30 o S
• Monsoon rainfall in Queensland, Australia
http://www.nasa.gov/mission_pages/hurricanes/features/AustraliaMonsoon.html
NWS Climate Prediction Center
http://www.cpc.ncep.noaa.gov/products/Global_Monsoons/Global-Monsoon.shtml
North American Monsoons
• Monsoons rainsalso affect the Southwest
• http://www.cpc.ncep.noaa.gov/products/Global_Monsoons/American_Monsoons/
When winds blow in certain directions, they may cause upwellings which move surface off-shore, bringing nutrient-rich water up, or downwellings which move water toward the shore and then downward, reducing bio-productivity.
http://www.iupui.edu/~g115/assets/mod10/updownwell_lg.jpg
