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Quantifying future precipitation changes in central Asia (CA), one of the largest semiarid‐to‐arid regions in the world, is increasingly attracting attention. Extreme precipitation changes in CA have been studied based on global climate models (GCMs) in the Coupled Model Intercomparison Project (CMIP). However, quantitative information regarding projected changes in extreme precipitation in CA under the 1.5–4°C global warming scenario is lacking; the potential advantages of the latest‐generation GCMs (i.e., CMIP6) in characterizing precipitation in CA have not been investigated. Thus, in this study, we evaluated the models' overall performance in reproducing the spatiotemporal pattern of four extreme precipitation indices and further performed an observationally constrained projection of changes in extreme precipitation indices for 1.5–4°C global warming based on a weighted multimodel ensemble. Regarding homologous models, CMIP6 models exhibited limited improvement relative to their earlier versions in CMIP5. We project that extreme precipitation indices in CA will increase approximately linearly as global warming increases, except for the consecutive dry days (CDD) index. The changes in precipitation intensity and accumulation exhibit robust consistency between models, whereas the signal of CDD changes is masked by the noise produced by intermodel uncertainties. The changes in the average annual accumulated and maximum 1‐day precipitation relative to the reference period (1981–2010) in CA are 12.0 and 14.2% at 3°C global warming (similar to late‐century warming projected based on current mitigation policies), respectively. Moreover, we demonstrate the advantage of the weighted scheme over the traditional unweighted scheme for multimodel ensemble projection. [ABSTRACT FROM AUTHOR]

Rice bean (Vigna umbellata) is an underexploited domesticated legume crop consumed for dietary protein in Asia, yet little is known about the genetic diversity of this species. Here, we present a high-quality reference genome for a rice bean landrace (FF25) built using PacBio long-read data and a Hi-C chromatin interaction map, and assess the phylogenetic position and speciation time of rice bean within the Vigna genus. We sequence 440 landraces (two core collections), and GWAS based on data for growth sites at three widely divergent latitudes reveal loci associated with flowering and yield. Loci harboring orthologs of FUL (FRUITFULL), FT (FLOWERING LOCUS T), and PRR3 (PSEUDO-RESPONSE REGULATOR 3) contribute to the adaptation of rice bean from its low latitude center of origin towards higher latitudes, and the landraces which pyramid early-flowering alleles for these loci display maximally short flowering times. We also demonstrate that copy-number-variation for VumCYP78A6 can regulate seed-yield traits. Intriguingly, 32 landraces collected from a mountainous region in South-Central China harbor a recently acquired InDel in TFL1 (TERMINAL FLOWER1) affecting stem determinacy; these materials also have exceptionally high values for multiple human-desired traits and could therefore substantially advance breeding efforts to improve rice bean. Rice bean is an underexploited legume crop that has many desirable properties against bio and abiotic stresses. Here, the authors report the genome assembly of this species, conduct population genetics studies and reveal the genetic variations associated with adaptation and yield traits. [ABSTRACT FROM AUTHOR]

Future precipitation changes impact the availability of water resources and related flood and drought events. Recent studies have focused on the variations in precipitation based on the Representative Concentration Pathways scenarios, which do not reflect the current mitigation commitments of the Paris Agreement to stabilize the global mean temperature below the 2.0°C threshold. This paper analyzes the Asian precipitation response to emissions scenarios from warming. This response is a result of the Intended Nationally Determined Contributions (INDC) pledges (as of August 2018), which would satisfy the Paris Agreement target over the next few decades. Our results demonstrate that by the end of 21st century, mean precipitation in Asia will increase by 12.9% (11.7–14.7%) for a delayed action (No‐policy) scenario, 8.0% (6.7–8.8%) for a continued mitigation action (continued INDC‐pledge) scenario, and 2.4% (1.9–3.5%) and 4.4% (3.7–5.4%) for scenarios that stabilize the global mean temperature at the 1.5 and 2.0°C levels, respectively. The spatial heterogeneity of precipitation changes, however, reflects the complexity of precipitation responses in future climate projections. Furthermore, heavy rainfall events will become stronger as warming increases; however, the trend of dry spell events varies depending on the region. Considering the impacts of precipitation‐related extremes, we determined that the projected population exposure to heavy rainfall and dry spell events will significantly increase in most Asian regions. Limiting warming to lower levels (such as 1.5 or 2.0°C) would reduce the population exposure to heavy rainfall, thereby avoiding impacts associated with precipitation extremes. These results contribute to an improved understanding of the risks related to future climate extremes. Such information is crucial for planning mitigation and adaptation activities in Asia, which is home to nearly 60% of the global population. [ABSTRACT FROM AUTHOR]

The evolution of regional arid/humid patterns caused by global climate change deserves attention. We investigated the changes in the area of arid/humid climate regions over Asia under the aegis of national-committed emission reductions to comply with the Paris Agreement using an ensemble of 17 global climate models (GCMs) from the Fifth Coupled Climate Model Intercomparison Project (CMIP5) archives. Our results indicated an overall trend towards aridity in a future warmer climate based on an aridity index (AI), defined as the ratio of precipitation to potential evapotranspiration (PET). In the future, the humid region will contract and the arid region and arid/humid transition zones will expand. Compared with the present period, arid/humid region switch is projected to occur in a land area of 2512.8 × 103 km2 over Asia under the Intended Nationally Determined Contributions (INDC)-pledge scenario. If global warming is controlled to the ambitious 2.0 °C and 1.5 °C scenarios instead of that of the INDC-pledge scenario, a decrease in the changes in the area of arid/humid regions by more than half would be expected. In addition, the arid/humid regions with continuous global warming are estimated to contract/expand greatly. Changes in the spatial pattern of the arid/humid zones over Asia show strong similarities between multi-model simulations, although there are some differences in detail. [ABSTRACT FROM AUTHOR]

National committed greenhouse gas emission reduction actions are the center of the Paris Agreement, and are known as 'Intended Nationally Determined Contributions' (INDC) that aim to slow down global warming. The climate response to INDC emission reduction is a focus in climate change science. In this study, data from 32 global climate models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) were applied to investigate the changes in the mean and extreme high temperatures in Central Asia (CA) under the INDC scenario above the present-day level. The results show that the magnitude of warming in CA is remarkably higher than the global mean. Almost all the regions in CA will experience more intense, more frequent, and longer-lasting extreme high-temperature events. In comparison with the INDC scenario, the reduced warming of the 2.0 °C/1.5 °C target scenarios will help avoid approximately 44-61%/65-80% of the increase in extreme temperature events in terms of the intensity, frequency, and duration in CA. These results contribute to an improved understanding of the benefits of limiting global warming to the 2.0 °C/1.5 °C targets, which is paramount for mitigation and adaptation planning.