Friction between Japan and China in the East China Sea has escalated this year to the point where jets on both sides have been scrambled and Chinese military vessels have locked their fire control radar onto their Japanese counterparts multiple times. The source of this tension is the Senkaku (as they are known in Japan) or Diaoyu (if you’re in China) Islands – specifically, who owns them.

The islands passed to American administration after World War II and then were returned to Japan in 1972. But China and Taiwan both claim them as their own. They’re uninhabited, and last year the Japanese government bought them from their private owners, effectively nationalizing them.

The Senkaku/Diaoyu Islands dispute is the most high-profile clash in the region at the moment, but Japan also has major maritime disputes with South Korea and Russia. And China and Taiwan are separately clashing with the Philippines, Brunei, Malaysia, Vietnam, and even India and the United States to some extent over the South China Sea.

Frankly, the number of maritime disputes and boundaries in question in East Asia can be difficult to follow. Fortunately The Economist has produced a short video introduction to the major areas in question, the various claims placed on them, and the important role that oil and natural gas fields play in fueling the fire.

The Allure of Potential Energy

An important factor in nearly all these disputes (subtracting the Northern Territories) is energy. There are large untapped off-shore oil and gas fields in both the East China and South China Seas, which promise riches to whomever is able to explore and develop them first. Japan claims that “China only starting expressing an interest [in the Senkaku Islands] when it began to seem that oil and gas might lie under the sea,” reports The Economist.

Accurate estimates of the underwater resources are difficult because detailed exploration has not yet been done, but the U.S. Energy Information Agency (EIA) estimates there are between 60 and 100 million barrels of oil and between one and two trillion cubic feet of natural gas reserves in the East China Sea and approximately 11 billion barrels of oil and 190 trillion cubic feet of natural gas reserves in the South China Sea.

Not pictured in the video – but still critical players in this drama – are India and the United States. As part of its “Look East Policy,” New Delhi is hoping to quench its growing thirst for energy by fostering closer relations with Southeast Asian countries, particularly Vietnam, and helping to develop their hydrocarbon resources.

“China’s and India’s overlapping interests in the potential energy wealth of the South China Sea could foster suspicions and misperceptions, exacerbate tensions and possibly even escalate to conflict if left unaddressed,” writes the Center for a New American Security’s Will Rogers.

Washington too has taken an interest in the dispute over fears that a more bellicose China might run roughshod over its neighbors and threaten freedom of commerce along some of the world’s busiest sea lanes.

The UN Convention on the Law of the Sea (which the United States has yet to ratify) is the international standard for establishing maritime boundaries but is not well suited for resolving existing disputes. Also, as The Economist notes, China and Taiwan’s claim in the South China Sea – the so called “nine-dashed line” – has “no basis in international law” and is instead based on historical precedent.

A Rising Tide Lifts All Boats?

A further complicating factor could be climate change. What happens if the already-tiny island chains on which some of these claims are based start disappearing all together thanks to sea level rise?

U.S. Navy Admiral Samuel J. Locklear III, head of U.S. Pacific forces, recently called climate change the biggest long-term threat that his command faces. “People are surprised sometimes,” he told the Boston Globe. “You have the real potential here in the not-too-distant future of nations displaced by rising sea level.”

“The island of Tarawa in Kiribati, they’re contemplating moving their entire population to another country because [it] is not going to exist anymore,” he said.

The highest point of the Spratly Islands, a major flashpoint in the South China Sea, is only four meters above sea level.

In 2007, the Intergovernmental Panel on Climate Change predicted a worst-case scenario of two feet of sea level rise by 2100 due to warming temperatures and ice melt. But there is some indication that those projections were too conservative and observed increases have been faster.

Rising sea levels could put these territorial disputes on even shakier ground if islands and atolls disappear beneath the waves. As complicated as the situation currently is, there’s even less precedent for dealing with submerged territory.