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Avena sterilis L. (A. sterilis) and Avena ludoviciana Dur. (A. ludoviciana) are extremely invasive weeds with strong competitive ability and multiple transmission routes. Both species can invade a variety of dryland crops, including wheat, corn, and beans. Asia, as the world's major food-producing continent, will experience significant losses to agricultural production if it is invaded by these weeds on a large scale. This study used the MaxEnt model and ArcGIS to map the distribution of suitable habitats of the two species in Asia under climate change conditions. The constructed model comprised four levels, with a total of 25 index-level indicator factors used to evaluate the invasion risk of the two species. The results showed that the distribution of suitable habitats for both Avena species was highly dependent on precipitation and temperature. Under climate warming conditions, although overall the total suitable area is predicted to decrease compared to the current period, there are still moderately or highly suitable areas. Asian countries need to provide early warning for areas with significant increases in moderate and highly suitable zones for these two species of weeds under the background of climate change. If there is already an invaded area or if the suitability of the original area is increased, this should be closely monitored, and control measures should be taken to prevent further spread and deterioration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Dryland ecosystems in the Great Lakes Region of Central Asia (GLRCA) are highly sensitive to climate change due to the climate of spring precipitation. Although shifts in vegetation phenology have been widely attributed to rising temperature, the effects of solar radiation and drought on phenology remain largely unknown. Understanding the mechanisms of vegetation phenology response to climatic factors is essential for assessing the impact of climate change on dryland ecosystems. In this study, we investigated the spatial and temporal variations of vegetation phenology across the GLRCA using a long-term series of Normalized Difference Vegetation Index (NDVI), and then examined the response of vegetation phenology to climate change within different climate zones by combining with climate data (surface temperature, soil moisture, short-wave radiation, and standardized precipitation evapotranspiration index (SPEI)). The results suggested that the start of growing season (SGS) and the end of growing season (EGS) were significantly earlier regionally by -0.143 days/year and -0.363 days/year, respectively. Because of changes in SGS and EGS, length of growing season (LGS) across the GLRCA was shortened at a rate of -0.442 days/yr, which was mainly attributed to advanced EGS. Additionally, SGS of vegetation was negatively correlated with surface temperature but positively correlated with soil moisture and SPEI. These results indicated that surface temperature was a major determinant of advanced spring phenology, while increased soil moisture and mitigated drought would delay spring phenology. The response of autumn phenology to surface temperature and short-wave radiation varied across different climate zones. In arid climate zone, autumn phenology was obviously advanced with the increase of surface temperature and short-wave radiation. In cold climate zone, higher surface temperature and short-wave radiation postponed autumn phenology. Meanwhile, the thermal growing season did not accurately characterize the actual vegetation growing season because GLRCA phenology was different from most of Northern Hemisphere., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Urbanization is one of the pivotal aspects of socioeconomic advancement which is critically vulnerable to climatic extremes. Extreme precipitation and urbanization are largely interlinked. Estimating the extreme precipitation-induced urban area exposure is the fundamental aspect of urban risk assessment for precipitation-related floods. In this study, future urban area exposure to extreme precipitation and associated influential factors are investigated over South Asia under 1.5 °C, 2.0 °C, 3.0 °C, and 4.0 °C global warming thresholds. In this regard, we used newly released 20 up-to-date climate models outputs, and five Integrated Assessment Models (IAMs) based urban land-use products under four combined scenarios of the Shared Socioeconomic Pathways and Representative Concentration Pathways (SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5) from the sixth phase of Coupled Model Intercomparison Project (CMIP6). Extreme precipitation is characterized by adopting 20-, 50-, and 100-year return periods of annual maximum daily precipitation. Results reveal a massive urban area expansion over South Asia which is the utmost by 186.4% under SSP3-7.0 than the reference period (1995-2014). The variations in projected urban areas mainly occur in Indo-Gangetic Plain (IGP) region among scenarios. In relative terms, extreme precipitation frequency and associated urban area exposure are prospective to increase with continued global warming. The exposed urban area varies 4.5- to 7.4-fold higher under different warming thresholds than the reference period. The leading increase is estimated (7.4-fold) under 4.0 °C. Notably, for global warming targets set out by the Paris Agreement (1.5 °C, and 2.0 °C), exposed urban area is intended to be 10.2% higher under 2.0 °C than 1.5 °C. Spatially, the exposed urban area will be dominant in the southeast region relative to the reference period. Importantly, the interaction effect (simultaneous change in climate-urban land) is the principal contributor to the changes in urban area exposure to extreme precipitation over South Asia. However, this study's findings strongly support the accomplishment of the Paris Agreement target and provide a scientific basis for formulating urban land-use policy interventions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

Vegetation is highly sensitive to climate changes in arid regions. The relationship between vegetation and climate changes can be effectively characterized by vegetation phenology. However, few studies have examined the vegetation phenology and productivity changes in arid Central Asia (ACA). The vegetation phenological information of ACA was extracted using MODIS NDVI (Normalized Difference Vegetation Index) data, and the dynamics of vegetation phenological changes under spatiotemporal variations were quantitatively assessed. Moreover, the impacts of climate change on vegetation phenology and net primary productivity were analyzed by combining meteorological data with that of MODIS NPP (Net Primary Productivity) during the same period. The results demonstrated that the start of the season (SOS) of vegetation in the study was concentrated from mid-February to mid-April, while the end of the season (EOS) was concentrated from early October to mid-December. The length of growing season (LOS) ranged from 6 to 10 months. The SOS of vegetation was gradually postponed at a rate of 0.16 d·year -1 . The EOS advanced at a rate of 0.69 d·year -1 . The LOS was gradually shortened at a rate of 0.89 d·year -1 . For each per 1000 m increase in elevation, the SOS of vegetation was postponed by 12.40 d; the EOS advanced by 0.40 d, and the LOS was shortened by 11.70 d. For the impacts of climate changes on vegetation phenology and NPP, the SOS of vegetation phenology negatively correlated with temperature but positively correlated with precipitation and NPP. The EOS and LOS positively correlated with temperature but negatively with precipitation and NPP. Results indicated that the SOS was not moved ahead but was delayed, while the EOS advanced rather than being postponed under climate change. These results can offer new insights on the phenological response to climate change in arid regions and on non-systematic changes in phenology under global warming., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The projections of mean temperature, precipitation (P), and potential evapotranspiration (PET) reflect the probabilities of long-term changes of hydrologic processes and induced extreme events. In this paper, we investigated the future changes in some pivotal climatic variables (mean temperature, precipitation, and potential evapotranspiration) under 1.5 °C, 2.0 °C, and 3.0 °C specific warming levels (SWLs) across the Indus River Basin of South Asia. The seven global climate models output under seven different emission scenarios (SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP4-3.4, SSP4-6.0, and SSP5-8.5) from the latest Sixth phase of Coupled Model Intercomparison Project (CMIP6) are used for this purpose. The Penman-Monteith approach is applied to estimate PET, and the water balance equation is for reflecting water surplus/deficit. Results indicate that except for precipitation, the greater increases in temperature and PET are inclined to happen with continued global warming. The highest increase in temperature is accounted for 14.6% (2.4 °C), and the enhanced PET is estimated at 5.2% higher than the reference period (1995-2014) under 3.0 °C SWL. While the precipitation is projected to increase by the highest 4.8% for 2.0 °C warming level. The differences in regional climate for an additional 0.5 °C (2.0-1.5 °C) and 1.0 °C (3.0-2.0 °C) of warming, the temperature is projected to increase by 0.4 °C and 0.9 °C in the entire IRB respectively. The highest increase in mean temperature (5.1%) and PET (2.4%) in the IRB are predicted to intensify for an additional 1.0 °C than that of 0.5 °C of warming, but precipitation is intended to decrease by 0.4%. Spatially, the increase in temperature, precipitation, and PET are dominated towards high elevation in the upper basin (north) under all the SWLs. The increased variability in climatological parameters across IRB depicts an evident occurrence of both wet events (upper basin) as well as dry events (lower basin) with the increase in global average temperature rise. However, these findings provide an insightful basis for water resource management as well as initiating mitigation and adaptation measures in the IRB related to water surplus (floods) and water deficit (droughts)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Abstract: In this paper, the long-term trends in surface temperature in several large Asian cities (Seoul, Tokyo, Osaka, Taipei, Manila, Bangkok, and Jakarta) have been analyzed for estimating the effects of urban warming. A new index, E-HII, is proposed: it is the value obtained by subtracting the temperature data of the four grids around the city from the observational temperature data in the city. Osaka shows the largest E-HII, increasing from approximately 2.4 °C in 1901 to almost 3 °C after 1981. The E-HIIs of Seoul, Tokyo, and Taipei, have increased by 1 °C to 2 °C. Jakarta and Bangkok exhibited a lower E-HII. E-HIIs of Manila and Bangkok have been increasing rapidly after 1961. [Copyright &y& Elsevier]

The RIHN project “Human impacts on urban subsurface environments” aims to suggest improved development plans of urban centers for human well-being. This will be done by examining reconstructed past changes in urban environments, and by developing integrated nature-social models. Subsurface environmental indicators are developed from the points of view of: (1) human activities; (2) climate change; and (3) character of urban development and social policies. Water, heat, and material environments and transport vectors are being evaluated by a number of different approaches. Some of these include investigating changes in groundwater resources using satellite observations, reconstructing effects of climate change and urbanization using subsurface thermal regimes, and evaluating past contamination patterns from preserved subsurface records. In this overview paper, we describe the current status of urbanization in Asia, subsurface water conditions, material and contaminant transport to surface waters by groundwater, and subsurface thermal anomalies due to the heat island effect. The rapid pace of urbanization in Asia requires that we develop a better understanding of how to deal with environmental impacts, both above and below ground. [Copyright &y& Elsevier]