West Pacific: Guam, Palau and Chuuk
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Guam, Palau, Chuuk
Figure 1. Guam, Palau and Chuuk locations (West Pacific area).
All these islands are located in the West Pacific area, where Co-ordinated Airborne
Studies in the Tropics (CAST) campaign is being held in January-February 2014. Guam was
chosen to be the CAST logistics and operations centre with the FAAM BAe-146 plane
deployment site. Both Palau and Chuuk will serve as stop-over stations for the BAe-146
aircraft during the sortie/science flights (Guam-Palau/Chuuk-Equator-Palau/Chuuk and
Palau/Chuuk-Equator-Palau/Chuuk-Guam).
Guam
Palau
Chuuk
Guam (the island of Guam) is the western most territory of the United States,
located approximately 3,300 miles west of Hawaii, 1,500 miles east of the Philippines and
1,550 miles south of Japan. It is an important US military outpost and also is famous for
catering large number of Asian tourists over the Chinese New Year celebrations and both
winter and summer holidays.
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Palau is an island country located in the western Pacific Ocean. It is geographically
part of the larger island group of Micronesia. The country's population of around 21,000 is
spread across 250 islands forming the western chain of the Caroline Islands. The most
populous island is Koror. The islands share maritime boundaries with Indonesia, the
Philippines, and the Federated States of Micronesia. Having voted against joining the
Federated States of Micronesia in 1979, the islands gained full sovereignty in 1994 with the
United States. Palau's economy is based mainly on tourism, subsistence agriculture and
fishing.
Chuuk is one of the four islands of the Federated States of Micronesia, and has
around half the population of the FSM. Despite this the capital of the federation is on
Pohnpei, which is not popular with the Chuukese. The population is overwhelmingly native
with the main language being Chuukese, although everybody speaks English. The main
tourist attraction is diving to look at the wrecks in the lagoon, but in fact the lagoon is
incredibly beautiful in its own right.
All these islands are situated in the West Pacific area of hugely varied atmospheric
circulation, including strong upwelling, deep convection events, region of anticyclone
formation and the presence of interseasonal and interannual atmospheric phenomena: El
Nino Southern Oscillation (ENSO) and Madden Julian Oscillation (MJO). This is one of the
reasons CAST is being held in Guam area. The CAST 2014 campaign will take place in 2014
over the West Pacific. This region, specifically Guam, was chosen for the primary base and
the location of Global Hawk and BAe-146 deployment, based on several factors. First and
foremost, Guam is located on the borderline of upwelling and downwelling zones. This
implies flights should be directed towards south to Chuuk and Palau, respectively, to
observe the potential strong convective motions. BAe-146 deployment in Guam will be
capable of reaching the area of strong marine convection just north of the equator.
Secondly, the West Pacific tropical zone is considered to be a location where most of air
mass from the troposphere, including both biogenic oceanic emissions and anthropogenic
emissions from the South Asia, enters the TTL and reaches stratosphere. Also, this area is
characterised by the large presence of oceanic algae and phytoplankton which produce
halogenated VSLS in vast amounts, which in turn means that elevated levels of these
compounds may reach the TTL and further affect the stratospheric ozone budget. These two
facts show how much of a global impact this area potentially has and this is why to monitor
changes in emissions within this area is a matter of the utmost importance.
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