Asia Community

This is an interesting article, fulltext here: https://doi.org/10.1029/2025EF005971

A Tale of Two Unprecedented Droughts in Southeast Asia: Physical Drivers and Impending Future Risks

Authored by: Shuping Ma, Xiao Peng, Xinyue Liu, Zhongwang Wei, Zhixiao Niu, Wenpeng Zhao, Ming Pan, Xiaogang He

Abstract: Conventional wisdom suggests that tropical droughts in Southeast Asia are closely linked to natural climate variability like El Niño. However, the extreme 2014 drought occurred independently of El Niño, suggesting other dynamic forcings at play. Here we use moisture budget analysis, moisture tracking, and physics-informed joint probability modeling to disentangle the interplay between dynamic and thermodynamic drivers behind this unprecedented drought and to assess future drought risks under climate change. We find that the 2014 drought primarily resulted from air subsidence due to anticyclone-driven mid-troposphere divergence, leading to significant precipitation deficits, which are further intensified by reduced marine moisture inflow from the West Pacific. Incorporating the dynamic and thermodynamic drivers into our bivariate probabilistic analysis, we find that the likelihood of 2014-like droughts will increase by 25% and 43% under stabilized and business as usual pathways, respectively, by mid-century (2030–2064). Such increases in drought risk are dominated by climate-change-induced changes in dynamic processes, particularly reduced mid-troposphere vertical motion, where thermodynamic processes and the dependence structure between the two play a less significant role. However, significant inter-model inconsistence in attributing the relative importance of these factors highlights the challenges of using current climate models for robust risk assessment.

Plain Language Summary
In early 2014, Southeast Asia experienced an extreme drought. Our analysis explores the role of the intricate interplay between dynamic and thermodynamic processes in drought formation. We find that the probability of experiencing droughts similar to the 2014 event increases by 25% under the SSP126 scenario compared to historical likelihood, and under the SSP585 scenario, this increase is even more pronounced at 43%, when employing vertical motion and relative humidity to describe the combined effect of the thermodynamic and dynamic processes. Overall, we anticipate a significant increase in the frequency of extreme drought conditions under more severe warming scenarios, with the dynamic factors mainly contributing to the increased likelihood of 2014-like droughts in the future.

Key Points

We explore the intricate interactions among the physical mechanisms that contribute to the historic 2014 Southeast Asia drought

The extreme drought, characterized by the interplay of vertical motion and relative humidity, has a “likely” return period of 95 years

The frequency of extreme drought conditions will increase by 25% and 43% under future scenarios, with dynamical factors playing a key role

A New Approach to Improving Drought Resilience in Desert Ecosystem Restoration
Recurring drought and accelerating desertification are placing increasing pressure on dryland ecosystems, leading to reduced vegetation cover, soil degradation, and the decline of essential ecosystem functions. Under these conditions, ecological restoration—ranging from soil stabilization to the re-establishment of protective plant cover—has become both urgent and increasingly challenging due to limited water availability.
One practical response to this challenge is the use of deep root-zone irrigation, a technique that delivers water directly to subsurface soil layers where plant roots are most active. By reducing surface wetting, this approach helps limit water losses through evaporation and runoff while improving plant access to moisture under drought conditions.
Building on this concept, our research team has applied the pipe method as a targeted deep-irrigation solution. In this method, irrigation water is conveyed through a perforated pipe and released within the root zone, creating a deeper and more stable moisture distribution compared with conventional surface irrigation. This results in more efficient water use, improved soil moisture conditions, and stronger plant establishment in water-limited environments.
The findings show that the pipe method can contribute to more resilient restoration outcomes by combining water savings with improved plant performance.
Details of this work have been published in the journal Land Degradation & Development.
https://doi.org/10.1002/ldr.70076

An interesting article worthwhile reading: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024EF005565

Great Green Wall in China -- I'm sharing a video titled "How China turned the desert into green forests" with an impressive story about ecosystems transformation with a large-scale master-planned forestation over vast desert lands to combat desertification in China. I've learned a bit more everytime when I read info about this "Great Green Wall" project, and hope you'll enjoy this one. I'm spreading it as part of my actions to take part in the UN World Soil Day 2025. The link goes: https://www.msn.com/en-us/news/world/how-china-turned-the-desert-into-g…

SKYWARN actions kickoff on Skywarn Recognition Day 2025
Today, December 6, is the SKYWARN Recognition Day (SRD) in the US. While the NOAA’s National Weather Service (NWS) cancelled the SRD 2025, as a registered Official Skywarn Spotter and a SciStarter participant in the SKYWARN citizen science project stationed at the Arcadia Ecohome in the foothill community of Arcadia, California, I'm taking on a weeklong voluntarily sky-watch of the San Gabriel Mountains, a desert mountain range just north of Arcadia, as part of my actions to take part in the celebrations of both the 2025 SRD on December 6, the first Saturday of December, and International Mountain Day on December 11, along with reporting and advocacy activities such as this writeup. Monitoring the sky over desert mountains in Southern California where unusual winter wildfires have occurred in recent years, such as the devastating ones in January 2025, driven by extreme drought and heat after wet years and strong Santa Ana winds, is becoming critical in the era of climate new normal with hazardous windstorms and firestorms for our attentions and actions as members of the Skywarn Weather Spotters Network and the Fire Adapted Communities Network (FAC Net).

Soil properties and soil biodiversity play significant roles in land degradation, especially in arid regions. Today is the UN World Soil Day (WSD) 2025 themed "Healthy Soils for Healthy Cities”. As an urban farmer and a USEPA recognized Qualify Water Efficient Landscaper (QWEL) working at the Arcadia Ecohome’s micro-agroforest, a Certified Bee Friendly Farm and a listed Climate Victory Garden, located in the arid Southern California, I’ve registered a local event with FAO to support the global celebrations of WSD. Our key actions taken today is focused on improving soil properties and biodiversity to combat land degradation with actions to add organic matters from fallen leaves, tree trimmings & food wastes to the forest floor through composting so as to enhance the soil sponge’s functions of taking and keeping moisture from cool night dews, to harbor a bio-diversified forest-floor inhabitants such as insects, earthworms & microbes who contribute to build healthy soils, to induce root growth for reducing soil erosion, and to minimize green & food wastes generated in urban areas to be hauled to remote desert landfills. The photo taken today (sorry, cannot be uploaded) shows sheet composting of fallen leaves all over the forest floor, pile composting of twigs & branches by tree roots and an in-ground composting of kitchen wastes, all for building healthy soils by nature-based solutions. I’m sharing what we do at CIEDM with our networks, especially my follow members in the United Nations Convention to Combat Desertification (UNCCD) Communities of Learning and Practice, as part of our grassroots actions in social media campaign for WSD.

Thanks for Suyu's warm welcome! As a new member of this community, I'm delighted to briefly introduce myself: I'm an academic and practitioner in the field of urban and environmental planning, with an interest in nature/resources/water conservation. I've lived and worked for 40+ years in the Los Angeles metropolitan area, a part of the arid US Southwest region, and on daily basis encountered/crossed challenges and news about drought, heatwaves, wildfires, flash floods and other climate issues in this region and beyond. With my Chinese ethnic origin, growup in Taiwan, and work & travel experiences in several parts of Asian, including serving as a faculty member in Saudi Arabia and China, I'm glad to be here to share and learn with all of you in this community.

New insights on declining natural carbon sinks

A new study published in Nature highlights how climate change and land-use pressures are reducing the Earth’s ability to absorb CO₂. The findings show that natural land sinks are weakening, while tropical forests in Southeast Asia and South America are shifting from carbon sinks to carbon sources, a trend driven by warming, drought, and deforestation.

Understanding these changes is essential for effective climate and drought management strategies.

Join the conversation and explore how stronger land stewardship and climate-resilient practices can support global mitigation efforts.

👉 Learn more and connect with the CLP community:
https://lnkd.in/ey3rv9Ga

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#UNCCDCLP #DroughtManagement #CommunityOfPractice #LearningCommunity #Desertification#LandDegradation #UNCCD
#Resilience #ClimateAdaptation #SustainableLandManagement #PeerLearning

This is an interesting article. Some people have the instinct that Pacific islands should have enough water due to their location (central in the ocean), but actually they also suffer from drought. This suggests that drought is indeed global and can affect all countries.

https://www.mdpi.com/2225-1154/13/9/172

Drought Monitoring to Build Climate Resilience in Pacific Island Countries
by Samuel Marcus, Andrew B. Watkins, andYuriy Kuleshov

Climate 2025, 13(9), 172; https://doi.org/10.3390/cli13090172
Submission received: 21 July 2025 / Revised: 20 August 2025 / Accepted: 22 August 2025 / Published: 26 August 2025
(This article belongs to the Special Issue Global Warming and Extreme Drought)

Abstract: Drought is a complex and impactful natural hazard, with sometimes catastrophic impacts on small or subsistence agriculture and water security. In Pacific Island countries, there lacks an agreed approach for monitoring agricultural drought hazard with satellite-derived remote sensing data. This study addresses this gap through a framework for agricultural drought monitoring in the Pacific using freely available space-based observations. Applying World Meteorological Organization’s (WMO) recommendations and a set of objective selection criteria, three remotely sensed drought indicators were chosen and combined using fuzzy logic to form a composite drought hazard index: the Standardised Precipitation Index, Soil Water Index, and Normalised Difference Vegetation Index. Each indicator represents a subsequential flow-on effect of drought on agriculture. The index classes geographic areas as low, medium, high, or very high levels of drought hazard. To test the drought hazard index, two case studies for drought in the western Pacific, Papua New Guinea (PNG), and Vanuatu, are assessed for the 2015–2016 El Niño-related drought. Findings showed that at the height of the drought in October 2015, 58% of PNG and 72% of Vanuatu showed very high drought hazard, compared to 6% and 40%, respectively, at the beginning of the drought. The hazard levels calculated were consistent with conditions observed and events that were reported during the emergency drought period. Application of this framework to operational drought monitoring will promote adaptive capacity and improve resilience to future droughts for Pacific communities.