Pub Date : 2024-07-22DOI: 10.1038/s41612-024-00716-z
Nail F. Bashan, Weiyu Li, Qi R. Wang
In an era where air pollution poses a significant threat to both the environment and public health, we present a network-based approach to unravel the dynamics of extreme pollution events. Leveraging data from 741 monitoring stations in the contiguous United States, we have created dynamic networks using time-lagged correlations of hourly particulate matter (PM2.5) data. The established spatial correlation networks reveal significant PM2.5 anomalies during the 2020 and 2021 wildfire seasons, demonstrating the approach’s sensitivity to detecting regional pollution phenomena. The methodology also provides insights into smoke transport and network response, highlighting the persistence of air quality issues beyond visible smoke periods. Additionally, we explored meteorological variables’ impacts on network connectivity. This study enhances understanding of spatiotemporal pollution patterns, positioning spatial correlation networks as valuable tools for environmental monitoring and public health surveillance.
{"title":"Dynamics of PM2.5 and network activity during extreme pollution events","authors":"Nail F. Bashan, Weiyu Li, Qi R. Wang","doi":"10.1038/s41612-024-00716-z","DOIUrl":"10.1038/s41612-024-00716-z","url":null,"abstract":"In an era where air pollution poses a significant threat to both the environment and public health, we present a network-based approach to unravel the dynamics of extreme pollution events. Leveraging data from 741 monitoring stations in the contiguous United States, we have created dynamic networks using time-lagged correlations of hourly particulate matter (PM2.5) data. The established spatial correlation networks reveal significant PM2.5 anomalies during the 2020 and 2021 wildfire seasons, demonstrating the approach’s sensitivity to detecting regional pollution phenomena. The methodology also provides insights into smoke transport and network response, highlighting the persistence of air quality issues beyond visible smoke periods. Additionally, we explored meteorological variables’ impacts on network connectivity. This study enhances understanding of spatiotemporal pollution patterns, positioning spatial correlation networks as valuable tools for environmental monitoring and public health surveillance.","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":null,"pages":null},"PeriodicalIF":8.5,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41612-024-00716-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141755305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-17DOI: 10.1038/s41612-024-00714-1
Jing Yang, Tao Zhu, Frederic Vitart, Bin Wang, Baoqiang Xiang, Qing Bao, June-Yi Lee
Heat extremes frequently hit different regions synchronously during boreal summer over the Eurasian continent. A remarkable coupling is first revealed between Eurasian heat extreme occurrence and individual extratropical intraseasonal oscillation (EISO). Further, the combined EISOs facilitate and largely increase the occurrence probabilities of synchronous Eurasian heat extremes. These dominant combined EISOs together contribute 20–45% to the total heat extreme days over the five Eurasian regions where the climatological heat extremes occur most frequently. A multi-model hindcast further shows that the subseasonal prediction exhibits higher skills for synchronous heat extremes over the combined-EISO hotspot regions when the associated combined EISOs are active, supporting the notion that the monitoring and prediction of EISOs are crucial for heat extremes’ early warning. Skillful prediction of EISOs opens a pathway for heat extremes’ prediction by extending it from the weather to the subseasonal timescales.
{"title":"Synchronous Eurasian heat extremes tied to boreal summer combined extratropical intraseasonal waves","authors":"Jing Yang, Tao Zhu, Frederic Vitart, Bin Wang, Baoqiang Xiang, Qing Bao, June-Yi Lee","doi":"10.1038/s41612-024-00714-1","DOIUrl":"10.1038/s41612-024-00714-1","url":null,"abstract":"Heat extremes frequently hit different regions synchronously during boreal summer over the Eurasian continent. A remarkable coupling is first revealed between Eurasian heat extreme occurrence and individual extratropical intraseasonal oscillation (EISO). Further, the combined EISOs facilitate and largely increase the occurrence probabilities of synchronous Eurasian heat extremes. These dominant combined EISOs together contribute 20–45% to the total heat extreme days over the five Eurasian regions where the climatological heat extremes occur most frequently. A multi-model hindcast further shows that the subseasonal prediction exhibits higher skills for synchronous heat extremes over the combined-EISO hotspot regions when the associated combined EISOs are active, supporting the notion that the monitoring and prediction of EISOs are crucial for heat extremes’ early warning. Skillful prediction of EISOs opens a pathway for heat extremes’ prediction by extending it from the weather to the subseasonal timescales.","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":null,"pages":null},"PeriodicalIF":8.5,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41612-024-00714-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141639653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-17DOI: 10.1038/s41612-024-00715-0
Lvfan Chen, Tianli Wang, Ashish Sinha, Fangyuan Lin, Huiru Tang, Hai Cheng, Richard Lawrence Edwards, Liangcheng Tan
Identifying tropical cyclone (TC) signatures in paleoclimate records enhances our understanding of long-term TC activity trends and the climatic factors influencing TC evolution. Stalagmites are considered promising archives for recording TC activity. However, despite the western North Pacific being the most TC-active ocean basin globally, it lacks stalagmite-based TC reconstructions. Here, we present a seasonally resolved stalagmite δ18O record from XRY cave in Southeast China, covering the period from 1951 to 2018 CE, to identify annual signals of strong TC activity. We propose that the minimum seasonal XRY δ18O value of each year can reconstruct regional TC activity, achieving an identification rate of 86% for strong TC years in study area. This demonstrates the feasibility of using stalagmites for TC reconstruction in Southeast China. Moreover, our research shows that inland stalagmites can still capture TC activity signals, which will promote the use of stalagmites in obtaining long-term records of post-landfall TC activity and inland impacts.
{"title":"A seasonally resolved stalagmite δ18O record indicates the regional activity of tropical cyclones in Southeast China","authors":"Lvfan Chen, Tianli Wang, Ashish Sinha, Fangyuan Lin, Huiru Tang, Hai Cheng, Richard Lawrence Edwards, Liangcheng Tan","doi":"10.1038/s41612-024-00715-0","DOIUrl":"10.1038/s41612-024-00715-0","url":null,"abstract":"Identifying tropical cyclone (TC) signatures in paleoclimate records enhances our understanding of long-term TC activity trends and the climatic factors influencing TC evolution. Stalagmites are considered promising archives for recording TC activity. However, despite the western North Pacific being the most TC-active ocean basin globally, it lacks stalagmite-based TC reconstructions. Here, we present a seasonally resolved stalagmite δ18O record from XRY cave in Southeast China, covering the period from 1951 to 2018 CE, to identify annual signals of strong TC activity. We propose that the minimum seasonal XRY δ18O value of each year can reconstruct regional TC activity, achieving an identification rate of 86% for strong TC years in study area. This demonstrates the feasibility of using stalagmites for TC reconstruction in Southeast China. Moreover, our research shows that inland stalagmites can still capture TC activity signals, which will promote the use of stalagmites in obtaining long-term records of post-landfall TC activity and inland impacts.","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":null,"pages":null},"PeriodicalIF":8.5,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41612-024-00715-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141639651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In mid-June to July 2023, North China witnessed extreme heatwaves, marked by intense near-surface warming with an advanced seasonal cycle of local air temperature. An unconventional upper-tropospheric cold vortex in early June, deviating from conventional “heat dome” patterns, preceded the heatwave extremes. The zonal SSTA gradient in Indo-Pacific warm pool initially suppressed Indian summer monsoon convection, which stimulated the cold vortex around North China via a tropical-extratropical teleconnection. This anomaly intensified the air-land thermal contrast, leading to increased sensible heating and reduced soil moisture in situ. The drier soil conditions maintained and further augmented sensible heating, escalating surface air temperature, and culminating in extraordinary heatwaves. The air column was then destabilized to mitigate the upper-level cold vortex. Historical records corroborate the extremity of the air-sea interactions in 2023. The ECMWF real-time subseasonal-to-seasonal (S2S) forecasts successfully capture the air-land feedback in both cold vortex and heatwave stages, albeit with an underestimation of heatwave intensity due to biases in soil moisture anomalies. Consequently, the initial cold vortex condition and air-land-sea interactions yield S2S predictability to the historic 2023 heatwaves in North China.
{"title":"Unconventional cold vortex as precursor to historic early summer heatwaves in North China 2023","authors":"Boqi Liu, Yanan Duan, Shuangmei Ma, Yuhan Yan, Congwen Zhu","doi":"10.1038/s41612-024-00718-x","DOIUrl":"10.1038/s41612-024-00718-x","url":null,"abstract":"In mid-June to July 2023, North China witnessed extreme heatwaves, marked by intense near-surface warming with an advanced seasonal cycle of local air temperature. An unconventional upper-tropospheric cold vortex in early June, deviating from conventional “heat dome” patterns, preceded the heatwave extremes. The zonal SSTA gradient in Indo-Pacific warm pool initially suppressed Indian summer monsoon convection, which stimulated the cold vortex around North China via a tropical-extratropical teleconnection. This anomaly intensified the air-land thermal contrast, leading to increased sensible heating and reduced soil moisture in situ. The drier soil conditions maintained and further augmented sensible heating, escalating surface air temperature, and culminating in extraordinary heatwaves. The air column was then destabilized to mitigate the upper-level cold vortex. Historical records corroborate the extremity of the air-sea interactions in 2023. The ECMWF real-time subseasonal-to-seasonal (S2S) forecasts successfully capture the air-land feedback in both cold vortex and heatwave stages, albeit with an underestimation of heatwave intensity due to biases in soil moisture anomalies. Consequently, the initial cold vortex condition and air-land-sea interactions yield S2S predictability to the historic 2023 heatwaves in North China.","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":null,"pages":null},"PeriodicalIF":8.5,"publicationDate":"2024-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41612-024-00718-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141618322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-13DOI: 10.1038/s41612-024-00712-3
Jakob Boyd Pernov, Eliza Harris, Michele Volpi, Tamara Baumgartner, Benjamin Hohermuth, Stephan Henne, William H. Aeberhard, Silvia Becagli, Patricia K. Quinn, Rita Traversi, Lucia M. Upchurch, Julia Schmale
Natural aerosols are an important, yet understudied, part of the Arctic climate system. Natural marine biogenic aerosol components (e.g., methanesulfonic acid, MSA) are becoming increasingly important due to changing environmental conditions. In this study, we combine in situ aerosol observations with atmospheric transport modeling and meteorological reanalysis data in a data-driven framework with the aim to (1) identify the seasonal cycles and source regions of MSA, (2) elucidate the relationships between MSA and atmospheric variables, and (3) project the response of MSA based on trends extrapolated from reanalysis variables and determine which variables are contributing to these projected changes. We have identified the main source areas of MSA to be the Atlantic and Pacific sectors of the Arctic. Using gradient-boosted trees, we were able to explain 84% of the variance and find that the most important variables for MSA are indirectly related to either the gas- or aqueous-phase oxidation of dimethyl sulfide (DMS): shortwave and longwave downwelling radiation, temperature, and low cloud cover. We project MSA to undergo a seasonal shift, with non-monotonic decreases in April/May and increases in June-September, over the next 50 years. Different variables in different months are driving these changes, highlighting the complexity of influences on this natural aerosol component. Although the response of MSA due to changing oceanic variables (sea surface temperature, DMS emissions, and sea ice) and precipitation remains to be seen, here we are able to show that MSA will likely undergo a seasonal shift solely due to changes in atmospheric variables.
{"title":"Pan-Arctic methanesulfonic acid aerosol: source regions, atmospheric drivers, and future projections","authors":"Jakob Boyd Pernov, Eliza Harris, Michele Volpi, Tamara Baumgartner, Benjamin Hohermuth, Stephan Henne, William H. Aeberhard, Silvia Becagli, Patricia K. Quinn, Rita Traversi, Lucia M. Upchurch, Julia Schmale","doi":"10.1038/s41612-024-00712-3","DOIUrl":"10.1038/s41612-024-00712-3","url":null,"abstract":"Natural aerosols are an important, yet understudied, part of the Arctic climate system. Natural marine biogenic aerosol components (e.g., methanesulfonic acid, MSA) are becoming increasingly important due to changing environmental conditions. In this study, we combine in situ aerosol observations with atmospheric transport modeling and meteorological reanalysis data in a data-driven framework with the aim to (1) identify the seasonal cycles and source regions of MSA, (2) elucidate the relationships between MSA and atmospheric variables, and (3) project the response of MSA based on trends extrapolated from reanalysis variables and determine which variables are contributing to these projected changes. We have identified the main source areas of MSA to be the Atlantic and Pacific sectors of the Arctic. Using gradient-boosted trees, we were able to explain 84% of the variance and find that the most important variables for MSA are indirectly related to either the gas- or aqueous-phase oxidation of dimethyl sulfide (DMS): shortwave and longwave downwelling radiation, temperature, and low cloud cover. We project MSA to undergo a seasonal shift, with non-monotonic decreases in April/May and increases in June-September, over the next 50 years. Different variables in different months are driving these changes, highlighting the complexity of influences on this natural aerosol component. Although the response of MSA due to changing oceanic variables (sea surface temperature, DMS emissions, and sea ice) and precipitation remains to be seen, here we are able to show that MSA will likely undergo a seasonal shift solely due to changes in atmospheric variables.","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":null,"pages":null},"PeriodicalIF":8.5,"publicationDate":"2024-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41612-024-00712-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141608174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-12DOI: 10.1038/s41612-024-00701-6
Kaiwen Li, Yu Huang, Kai Liu, Ming Wang, Fenying Cai, Jianxin Zhang, Niklas Boers
The comprehensive understanding of propagation patterns of extreme precipitation events (EPEs) is essential for early warning of associated hazards such as floods and landslides. In this study, we utilize climate networks based on an event synchronization measure to investigate the propagation patterns of EPEs over the global land masses, and identify 16 major propagation pathways. We explain them in association with regional weather systems, topographic effects, and travelling Rossby wave patterns. We also demonstrate that the revealed propagation pathways carry substantial EPE predictability in certain areas, such as in the Appalachian, the Andes mountains. Our results help to improve the understanding of key propagation patterns of EPEs, where the global diversity of the propagated patterns of EPEs and corresponding potential predictability provide prior knowledge for predicting EPEs, and demonstrate the power of climate network approaches to study the spatiotemporal connectivity of extreme events in the climate system.
{"title":"Key propagation pathways of extreme precipitation events revealed by climate networks","authors":"Kaiwen Li, Yu Huang, Kai Liu, Ming Wang, Fenying Cai, Jianxin Zhang, Niklas Boers","doi":"10.1038/s41612-024-00701-6","DOIUrl":"10.1038/s41612-024-00701-6","url":null,"abstract":"The comprehensive understanding of propagation patterns of extreme precipitation events (EPEs) is essential for early warning of associated hazards such as floods and landslides. In this study, we utilize climate networks based on an event synchronization measure to investigate the propagation patterns of EPEs over the global land masses, and identify 16 major propagation pathways. We explain them in association with regional weather systems, topographic effects, and travelling Rossby wave patterns. We also demonstrate that the revealed propagation pathways carry substantial EPE predictability in certain areas, such as in the Appalachian, the Andes mountains. Our results help to improve the understanding of key propagation patterns of EPEs, where the global diversity of the propagated patterns of EPEs and corresponding potential predictability provide prior knowledge for predicting EPEs, and demonstrate the power of climate network approaches to study the spatiotemporal connectivity of extreme events in the climate system.","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":null,"pages":null},"PeriodicalIF":8.5,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41612-024-00701-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141597453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-11DOI: 10.1038/s41612-024-00702-5
Jacob L. Gunnarson, Malte F. Stuecker, Sen Zhao
Under anthropogenic warming, future changes to climate variability beyond specific modes such as the El Niño-Southern Oscillation (ENSO) have not been well-characterized. In the Community Earth System Model version 2 Large Ensemble (CESM2-LE) climate model, the future change to sea surface temperature (SST) variability (and correspondingly marine heatwave intensity) on monthly timescales and longer is spatially heterogeneous. We examined these projected changes (between 1960–2000 and 2060–2100) in the North Pacific using a local linear stochastic-deterministic model, which allowed us to quantify the effect of changes to three drivers on SST variability: ocean “memory” (the SST damping timescale), ENSO teleconnections, and stochastic noise forcing. The ocean memory declines in most areas, but lengthens in the central North Pacific. This change is primarily due to changes in air-sea feedbacks and ocean damping, with the shallowing mixed layer depth playing a secondary role. An eastward shift of the ENSO teleconnection pattern is primarily responsible for the pattern of SST variance change.
{"title":"Drivers of future extratropical sea surface temperature variability changes in the North Pacific","authors":"Jacob L. Gunnarson, Malte F. Stuecker, Sen Zhao","doi":"10.1038/s41612-024-00702-5","DOIUrl":"10.1038/s41612-024-00702-5","url":null,"abstract":"Under anthropogenic warming, future changes to climate variability beyond specific modes such as the El Niño-Southern Oscillation (ENSO) have not been well-characterized. In the Community Earth System Model version 2 Large Ensemble (CESM2-LE) climate model, the future change to sea surface temperature (SST) variability (and correspondingly marine heatwave intensity) on monthly timescales and longer is spatially heterogeneous. We examined these projected changes (between 1960–2000 and 2060–2100) in the North Pacific using a local linear stochastic-deterministic model, which allowed us to quantify the effect of changes to three drivers on SST variability: ocean “memory” (the SST damping timescale), ENSO teleconnections, and stochastic noise forcing. The ocean memory declines in most areas, but lengthens in the central North Pacific. This change is primarily due to changes in air-sea feedbacks and ocean damping, with the shallowing mixed layer depth playing a secondary role. An eastward shift of the ENSO teleconnection pattern is primarily responsible for the pattern of SST variance change.","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":null,"pages":null},"PeriodicalIF":8.5,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41612-024-00702-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141584525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-05DOI: 10.1038/s41612-024-00709-y
Xiao Pan, Tim Li, Jinhua Yu
A shift of El Niño onset location from eastern Pacific (EP) to western Pacific (WP) occurred around 1970. It was accompanied by a faster mean sea surface temperature (SST) warming in WP and a change of precursory SST and wind anomaly patterns. The eigenvalue analysis of a simple coupled model shows that an SST anomaly (SSTA) in WP may grow under the post-1970 mean condition but cannot under the pre-1970 mean condition. As a result, a warm SSTA appeared in WP accompanying to a preceding La Niña condition in EP after 1970, whereas such a warming was rarely seen before 1970. The preceding SSTA patterns led to distinctive zonal wind responses in EP, favoring El Niño onset in EP prior to 1970. For the post-1970 El Niño onset, an initial warming in WP was induced by anomalous downward solar radiation in association with atmospheric meridional overturning circulation or anomalous horizontal advection associated with thermocline induced eastward geostrophic currents.
{"title":"Change of El Niño onset location around 1970","authors":"Xiao Pan, Tim Li, Jinhua Yu","doi":"10.1038/s41612-024-00709-y","DOIUrl":"10.1038/s41612-024-00709-y","url":null,"abstract":"A shift of El Niño onset location from eastern Pacific (EP) to western Pacific (WP) occurred around 1970. It was accompanied by a faster mean sea surface temperature (SST) warming in WP and a change of precursory SST and wind anomaly patterns. The eigenvalue analysis of a simple coupled model shows that an SST anomaly (SSTA) in WP may grow under the post-1970 mean condition but cannot under the pre-1970 mean condition. As a result, a warm SSTA appeared in WP accompanying to a preceding La Niña condition in EP after 1970, whereas such a warming was rarely seen before 1970. The preceding SSTA patterns led to distinctive zonal wind responses in EP, favoring El Niño onset in EP prior to 1970. For the post-1970 El Niño onset, an initial warming in WP was induced by anomalous downward solar radiation in association with atmospheric meridional overturning circulation or anomalous horizontal advection associated with thermocline induced eastward geostrophic currents.","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":null,"pages":null},"PeriodicalIF":8.5,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41612-024-00709-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141553389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Third Pole (TP) is the world’s largest highland and has one of the biggest reservoirs of glacier ice mass and snow cover on the Earth. Three major Asian rivers (the Indus, Ganga and Brahmaputra) are nourished by the melting of glaciers and snow in Central Himalaya, which are inevitable for the socioeconomic sustainability and water security of South Asia. Here, we investigate the long-term (1980–2020) changes in snow depth and precipitation in TP, where major precipitation occurs in the form of rainfall in summer, and snowfall in winter and spring. The seasonal mean snow depth is deep (≥1 m) in winter and shallow (≤0.2 m) in summer. The average snowmelt and snow water equivalent are higher in the central and western Himalaya and Karakoram ranges in spring, which are the regions with most glaciers in TP. There is a significant positive trend in total precipitation, about 0.01–0.03 mm d−1 yr−1 in the central and eastern TP during the South Asian Summer Monsoon for the 1980–2020 period. Snowmelt is also increasing (>0.5 × 10−3 mm yr−1) in the western Himalaya during spring, which is consistent with the temperature rise (0.04–0.06 °C yr−1) there. In addition, there is a notable increase in the annual mean glacier melt (here, the water equivalent thickness) in TP (−1 to −5 cm w.e. yr−1), with its highest values in the eastern and central Himalaya (−3 to −5 cm w.e. yr−1), as estimated for the period 2003–2020. On top of these, by the end of the 21st century, the Coupled Model Intercomparison Project Phase 6 (CMIP6) projections show that there would be a significant decrease in snow depth and an increase in temperature of TP in all shared socioeconomic pathways (SSPs). Henceforth, the increasing trend in temperature and melting of snow/glaciers in TP would be a serious threat to the regional climate, water security and livelihood of the people of South Asia.
第三极(TP)是世界上最大的高地,也是地球上最大的冰川和积雪宝库之一。亚洲三条主要河流(印度河、恒河和雅鲁藏布江)都受到喜马拉雅中部冰川和积雪融化的滋养,这对于南亚社会经济的可持续发展和水安全是不可避免的。在此,我们研究了主要降水形式为夏季降雨和冬春降雪的大埔地区雪深和降水量的长期(1980-2020 年)变化。冬季的季节平均积雪深度较深(≥1 米),夏季较浅(≤0.2 米)。喜马拉雅山脉中西部和喀喇昆仑山脉春季的平均融雪量和雪水当量较高,而这两个地区是总降水量中冰川最多的地区。1980-2020 年南亚夏季季风期间,大洋洲中部和东部的总降水量呈明显的正增长趋势,约为 0.01-0.03 mm d-1 yr-1。喜马拉雅山西部春季融雪也在增加(0.5 × 10-3 mm yr-1),这与该地区的气温上升(0.04-0.06 °C yr-1)相一致。此外,根据对 2003-2020 年期间的估算,热带雨林年平均冰川融化量(此处指水当量厚度)明显增加(-1 至-5 厘米(湿重)/年-1),喜马拉雅东部和中部的冰川融化量最高(-3 至-5 厘米(湿重)/年-1)。此外,根据耦合模式相互比较项目第 6 阶段(CMIP6)的预测,到 21 世纪末,在所有共同的社会经济路径(SSPs)中,积雪深度将显著减少,而热带降雨量的温度将上升。因此,大倾角地区气温上升和积雪/冰川融化的趋势将对区域气候、水安全和南亚人民的生计构成严重威胁。
{"title":"Observed changes in the climate and snow dynamics of the Third Pole","authors":"Jayanarayanan Kuttippurath, Vikas Kumar Patel, Babu Ram Sharma","doi":"10.1038/s41612-024-00710-5","DOIUrl":"10.1038/s41612-024-00710-5","url":null,"abstract":"The Third Pole (TP) is the world’s largest highland and has one of the biggest reservoirs of glacier ice mass and snow cover on the Earth. Three major Asian rivers (the Indus, Ganga and Brahmaputra) are nourished by the melting of glaciers and snow in Central Himalaya, which are inevitable for the socioeconomic sustainability and water security of South Asia. Here, we investigate the long-term (1980–2020) changes in snow depth and precipitation in TP, where major precipitation occurs in the form of rainfall in summer, and snowfall in winter and spring. The seasonal mean snow depth is deep (≥1 m) in winter and shallow (≤0.2 m) in summer. The average snowmelt and snow water equivalent are higher in the central and western Himalaya and Karakoram ranges in spring, which are the regions with most glaciers in TP. There is a significant positive trend in total precipitation, about 0.01–0.03 mm d−1 yr−1 in the central and eastern TP during the South Asian Summer Monsoon for the 1980–2020 period. Snowmelt is also increasing (>0.5 × 10−3 mm yr−1) in the western Himalaya during spring, which is consistent with the temperature rise (0.04–0.06 °C yr−1) there. In addition, there is a notable increase in the annual mean glacier melt (here, the water equivalent thickness) in TP (−1 to −5 cm w.e. yr−1), with its highest values in the eastern and central Himalaya (−3 to −5 cm w.e. yr−1), as estimated for the period 2003–2020. On top of these, by the end of the 21st century, the Coupled Model Intercomparison Project Phase 6 (CMIP6) projections show that there would be a significant decrease in snow depth and an increase in temperature of TP in all shared socioeconomic pathways (SSPs). Henceforth, the increasing trend in temperature and melting of snow/glaciers in TP would be a serious threat to the regional climate, water security and livelihood of the people of South Asia.","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":null,"pages":null},"PeriodicalIF":8.5,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41612-024-00710-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141553431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recently, nitrate (NO3–) levels in winter pollution in eastern China have been increasing yearly and have become the main component of PM2.5. The factors contributing to this rise in surface NO3– concentrations remain unclear, complicating the development of targeted pollution control measures. This study utilizes observational data from Shanghai during the winter 2019, alongside box model simulations, to recreate the NO3− pollution event and identify the key factors in the growth process. The analysis demonstrated that a rise in winter ozone levels significantly promotes NO3– production by facilitating NOx conversion via gas-phase and heterogeneous reactions. These findings could explain the correlation between the synchronous increase of surface ozone and NO3− in recent years. Furthermore, simulation of control strategies for NOx and volatile organic compounds (VOCs) identified an approach centered on ozone reduction as notably effective in mitigating winter NO3– pollution in the Yangtze River Delta.
{"title":"Nitrate pollution deterioration in winter driven by surface ozone increase","authors":"Zekun Zhang, Bingqing Lu, Chao Liu, Xue Meng, Jiakui Jiang, Hartmut Herrmann, Jianmin Chen, Xiang Li","doi":"10.1038/s41612-024-00667-5","DOIUrl":"10.1038/s41612-024-00667-5","url":null,"abstract":"Recently, nitrate (NO3–) levels in winter pollution in eastern China have been increasing yearly and have become the main component of PM2.5. The factors contributing to this rise in surface NO3– concentrations remain unclear, complicating the development of targeted pollution control measures. This study utilizes observational data from Shanghai during the winter 2019, alongside box model simulations, to recreate the NO3− pollution event and identify the key factors in the growth process. The analysis demonstrated that a rise in winter ozone levels significantly promotes NO3– production by facilitating NOx conversion via gas-phase and heterogeneous reactions. These findings could explain the correlation between the synchronous increase of surface ozone and NO3− in recent years. Furthermore, simulation of control strategies for NOx and volatile organic compounds (VOCs) identified an approach centered on ozone reduction as notably effective in mitigating winter NO3– pollution in the Yangtze River Delta.","PeriodicalId":19438,"journal":{"name":"npj Climate and Atmospheric Science","volume":null,"pages":null},"PeriodicalIF":8.5,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41612-024-00667-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141537085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}