“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