“SHRINKING SNOWCAPS AND RISING
TIDES – THE RESPONSE OF THE ARABIAN
SEA ECOSYSTEM TO CLIMATE CHANGE”
Joaquim Goes and Annette Decharon
Originally 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/themonsoon-over-himalayas
Uplift of the Himalayas “Sparked”
Monsoons in SE Asia
• Uplift began about 50
million years ago as
“India” collided with
“Asia”
• “Continentalcontinental 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 N30 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/GlobalMonsoon.shtml
North American Monsoons
• Monsoons rains
also affect the
Southwest
• http://www.cpc.ncep.
noaa.gov/products/Gl
obal_Monsoons/Ameri
can_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