The Barak River catchment, a steep and transboundary hydrological system shared between India and Bangladesh, sustains millions of people by providing water for domestic use, agriculture, fisheries, livelihoods, and forms a critical component of the Barak-Meghna basin. Despite its high exposure to extreme rainfall, long-term event-based assessments of monsoon rain-spell behaviour in this region remain limited. This work provides a comprehensive analysis of rain-spell characteristics, including maximum spell volume (V max ), peak intensity (R max ), and duration (D max ), using daily rainfall data spanning 1951-2024. Rain-spell behaviour is analyzed across 2 climatic epochs (pre-1980 and post-1980) using spatial generalized extreme value (GEV) modelling for multiple return periods to detect shifts in extreme rainfall regimes. Results reveal basin-wide reductions in V max (-15 to -25%) and D max (-10 to -20%), indicating shorter and less persistent monsoon spells, alongside localized intensification of R max (+15 to +30%) in orographic uplands. These contrasting trends suggest a shift toward a more convectively dominated monsoon regime, characterized by sharper runoff peaks, reduced infiltration, and declining baseflow. The pronounced contrast between upland intensification and downstream loss of rainfall persistence highlights an emerging pattern of compound flood-drought risk in this transboundary basin. By providing a spatially explicit extreme-value assessment of rain-spell dynamics in the Barak-Meghna system, this study offers a critical foundation for adaptive, non-stationary, and transboundary water-management strategies aimed at strengthening climate resilience under an evolving monsoon climate.
Coastal populations in Southeast Asia are highly vulnerable to climate change impacts. This systematic review synthesizes peer-reviewed literature from 2020-2025 retrieved from Web of Science, Scopus, and Google Scholar, focusing on climate change adaptation strategies in 10 Southeast Asian coastal countries. Eligible studies (n = 51) were analyzed through thematic coding, identifying 104 distinct adaptation strategies across 7 themes: ecosystem-based adaptation (21%), livelihood diversification (19%), early warning systems and disaster preparedness (16%), climate-resilient agriculture and fisheries (14%), infrastructure-based adaptation (11%), marine resource management and co-governance (10%), and traditional and indigenous practices (9%). Key adaptation strategies included mangrove restoration (reduces erosion and storm surges), sustainable aquaculture, disaster preparedness, and livelihood diversification (mitigates income loss from saline intrusion). Ecosystem-based and livelihood diversification approaches improve ecological stability, financial security, and community adaptive capacity, strengthening overall resilience. However, their long-term sustainability remains uncertain due to limited long-term evaluations, insufficient cost-effectiveness analysis, and weak alignment with national policies; in fact, most initiatives remain project-specific with limited evaluation of long-term effectiveness or cost-efficiency. Furthermore, equity considerations such as gender, poverty, and resource access are insufficiently integrated, potentially excluding marginalized groups. A critical gap persists between community-led innovations and national or regional adaptation frameworks, raising questions of scalability, funding, and policy alignment with national adaptation plans and nationally determined contributions. This review identifies the need for inclusive, equity-focused, and longitudinal research that links grassroots strategies with governance structures, ensuring sustained climate resilience for Southeast Asian coastal communities.
This study explores the connection between key meteorological variables and malaria incidence across Africa, addressing a critical gap in understanding how climate patterns influence disease persistence. Employing Climatic Research Unit gridded time series (CRU_TS) climate data (1981-2024), we established the K Malaria Index (KMI), an integrated quantity of climatic suitability for Plasmodium falciparum transmission based on a temperature-dependent extrinsic incubation period (EIP) and rainfall thresholds for mosquito breeding. Spatial analysis showed that regions with mean temperatures >18 degrees C and monthly rainfall >= 80 mm, predominantly in Central, West, and parts of East Africa, have the highest and most persistent transmission suitability. A significant long-term warming trend (+0.14 degrees C decade-1) links with a shortening of the EIP, enhancing transmission potential. Time-series validation shows that the KMI and its component variables have significant positive correlations with past malaria mortality rates, confirming its advantage as a predictive tool. The findings highlight the necessity of incorporating climate forecasts into public health planning to build effective and robust malaria control strategies under global warming.
