South Asia and the Pacific: Deficits to occur in W Thailand, Indonesia

30 October 2023

THE BIG PICTURE
The 12-month forecast ending in June 2024 anticipates near-normal conditions throughout most of Mainland and Maritime Southeast Asia, but isolated pockets of deficits are expected in western Thailand and some Indonesian islands. Surpluses are anticipated in eastern Thailand and Cambodia.

The map on top depicts long-term deficit and surplus anomalies as of September 2023, while the map on the bottom depicts a forecast of long-term deficit and surpluses as of June 2024.

Severe to extreme surpluses are expected in the following regions:

Eastern Thailand, in areas near the city of Sakhon Nakhon.
Northern Cambodia, in areas north of Tonlé Sap.
Northeastern Papua, in much of the Tolikara Regency.

Deficits of severe to exceptional intensity are expected in:

Western Thailand, appearing in the state of Lamphun and continuing in pockets down to areas of the Kanchanaburi Province.
The Indonesian island of Sumatra, primarily in southeastern coastal regions. Similarly intense deficits are expected throughout much of Java.

Moderate to severe deficits are anticipated in:

The Philippines, primarily in the southern island of Mindanao.

The 3-month maps (below) show the evolving conditions in more detail.

FORECAST BREAKDOWN
The forecast through December 2023 indicates that much of Maritime Southeast Asia will experience severe to exceptional deficits, with the highest concentrations appearing in the Indonesian islands, particularly along the coasts of Sumatra, throughout Java, western to northern Kalimantan, and central Sulawesi. Western coastal regions of Thailand are expected to observe extreme to exceptional surplus, as well as its provinces of Khon Kaen and Mukdahan. Further south, regions of northern Cambodia, northeast of the Tonlé Sap, will experience severe to extreme surplus.

From January through March 2024, moderate to severe deficits are expected to occur throughout most southern islands of the Philippines. Extreme to exceptional deficits are expected to continue in Java, but are expected to downgrade in magnitude considerably, isolating into western coastal regions of the island and coastal regions of the Malang Regency. Extreme to exceptional surplus is expected in western coastal regions of Thailand, as well as in the provinces of Khon Kaen and Mukdahan. Moderate to severe transitional conditions are also expected in isolated areas of Thailand’s western coastal regions, which continue into southern Myanmar.

The forecast for the final months – April 2024 through June 2024 – anticipates near-normal conditions for most of Maritime and Mainland Southeast Asia, though moderate surplus is expected to continue in the Malaysian state of Sarawak, and moderate deficit occurring throughout the majority of the Philippines.

Please note that WSIM forecast skill declines with longer lead times.

IMPACTS
Indonesia is experiencing its most severe dry season in four years, with consequential wildfires putting the country’s production of palm oil, coffee, and rice at risk. Indonesia usually observes hotter, drier weather when El Niño occurs, such as in 2015 and 2019, when the country saw the lowest levels of aggregated precipitation in over two decades, according to Gro’s Climate Risk Navigator for Agriculture. So far in October, precipitation is 45% below the 10-year average.

Thailand has launched cloud-seeding projects to combat drought as the country deals with severe water scarcity. Rainfall has been scarce due to El Nino, prompting the government to seek cloud-seeding operations in the province of Lop Buri at the end of September. The drought has fueled worries of compromised agricultural production, which is a key industry for the country. The Ministry of Agriculture and Cooperatives estimates that rice production will decline to 25.8 million tonnes for 2023-2024, down more than 3% from last season. As the country faces intense water shortages, dams and reservoirs were reportedly only 54% full as of October 3rd, storing about 28.3 billion cubic meters of water.

According to the ISEAS-Yusof Ishak Institute’s Climate Outlook Survey 2023, Southeast Asians are becoming increasingly worried about long-term food security exacerbated by climate change. The survey was conducted from July to August after intense heat waves occurred in the region months earlier, but before the price of rice increased by 20 to 30 percent due to drought-related decline in production. Residents of the Philippines expressed their worry most strongly, as more than half categorized themselves as “very concerned” and another 33.2 percent as “somewhat concerned.” By some accounts, the Philippines ranks as the top country in the world in disaster risk globally, with Indonesia and Myanmar also in the top 6.

NOTE ON ADMINISTRATIVE BOUNDARIES
There are numerous regions around the world where country borders are contested. ISciences depicts country boundaries on these maps solely to provide some geographic context. The boundaries are nominal, not legal, descriptions of each entity. The use of these boundaries does not imply any judgement on the legal status of any territory, or any endorsement or acceptance of disputed boundaries on the part of ISciences or our data providers.

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