Bits from several sources:
"More than 600 vessels a day, many of them oil tankers and cargo ships, use the straits of Malacca and Singapore. Together, the straits are the main maritime link between the Indian and Pacific oceans, via the South China and Andaman seas... the world's busiest shipping lane ...Half of the world’s pirate attacks happen in or near the Strait of Malacca
...The world's most piracy infested channel is in fact, the Strait of Malacca between Malaysia and Indonesia. More than two thirds of the attacks reported to the International Maritime Bureau (IMB), a division of the International Chamber of Commerce (ICC), are in Asian waters. Reported incidents have tripled since the early 1990s and the first half of 2003 was the worst 6 month period on record with 234 pirate attacks and 16 deaths and 52 injured worldwide. There were also 193 crew members held hostage during this period.
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Oil Flows (1999E): 10.3 million bbl/d
Destination of Oil Exports: Japan, South Korea, China, other Pacific Rim countries.
Main Concerns: The Strait of Malacca, linking the Indian and Pacific Oceans, is the shortest sea route between three of the world's most populous countries -- India, China, and Indonesia -- and therefore is considered to be the key choke point in Asia. The narrowest point of this shipping lane is the Phillips Channel in the Singapore Strait, which is only 1.5 miles wide at its narrowest point. This creates a natural bottleneck, with the potential for a collision, grounding, or oil spill (in addition, piracy is a regular occurrence in the Singapore Strait). If the strait were closed, nearly half of the world's fleet would be required to sail further, generating a substantial increase in the requirement for vessel capacity. All excess capacity of the world fleet might be absorbed, with the effect strongest for crude oil shipments and dry bulk such as coal. Closure of the Strait of Malacca would immediately raise freight rates worldwide. More than 50,000 vessels per year transit the Strait of Malacca. With Chinese oil imports from the Middle East increasing, the Strait of Malacca is likely to grow in strategic importance in coming years.Attacks on Chemical Ships in Southeast Asia Seem to Be Piracy, Not Terror The New York Times March 27, 2003
Piracy attacks in the Malacca Straits
News & Articles on Strait of Malacca
A Tale of Two Centuries: The Globalisation of Maritime Raiding and Piracy in Southeast Asia... (James F. Warren)
Piracy in Southeast Asia: a global comparison (Ger Teitler)
The steadiest current is the inflow through the Malacca Straits, averaging around 1/3-2 knots through the year. The monsoons controls the currents elswhere, driving inflow waters from the Bay of Bengal through the western channels from June to August during the southwest monsoon. This also pushes the Malaccan inflow against the Sumatran coast and forces some Andaman sea water through the Straits. When these winds die southwestward currents gradually form that are maintained and enhanced by the northeast monsoon from December through February. A more sudden shift is seen from March through May when the southwest monsoons begins anew.