The economic loss suffered by the Pacific region could range from 2.9% to as high as 12.7% of annual GDP by 2100, according to Economics of Climate Change in the Pacific, a new study from the Asian Development Bank (ADB) that was published recently.

According to the report, the most significant economic losses would be felt in Papua New Guinea (PNG), where climate change impacts could trigger a loss of up to 15.2% of its GDP by 2100. Timor-Leste’s GDP is predicted to drop by up to 10%, followed by Vanuatu at 6.2%, Solomon Islands at 4.7%, Fiji at 4.0% and Samoa at 3.8%.

Under a medium emissions scenario, Fiji, PNG, Samoa, Solomon Islands, Timor-Leste and Vanuatu could see temperatures rise by 2-3^oC by 2070, which could lead to significant decreases in rain-fed agriculture, reduced fish catches, widespread coral bleaching, and falling tourism numbers.

The report notes that the negative effect on agriculture contributes to most of the total economic cost of climate change in the Pacific, and estimates that the Pacific region could require $447 million on average until 2050, and up to $775 million or 2.5% of GDP per year to prepare for the worst scenario. The cost of adaptation would be significantly less under lower emissions scenarios.

The report recommends policy leaders take urgent action to mainstream climate change mitigation into development planning and develop forward-looking adaptation strategies. The report also recommends climate-proofing infrastructure to improve long-term sustainability and boosting capacity of Pacific countries to deal with climate change on their own. Pacific countries will also need dramatically improved access to global and regional climate change funds.

Economics of Climate Change in the Pacific includes modeling of future climate over the Pacific region, assessments of the potential impacts on agriculture, fisheries, tourism, coral reefs, and human health, and predictions of the potential economic impact of climate change for specific sectors and economies under various emissions scenarios.

“It is critical that countries contributing to the problem of climate change step up to assist Pacific friends and neighbors in the fight to protect their countries against natural disasters, crop losses, and forced migration,” said Xianbin Yao, Director General of ADB’s Pacific Department. “Our findings show that if not adequately addressed, climate change could overturn the region’s development achievements.”

Tonga was not mentioned in the report, and according to the ADB Sydney office, no data was available on Tonga.