Judith A. Rosentreter, Lewis Alcott, Taylor Maavara, Xin Sun, Yong Zhou, Noah J. Planavsky, Peter A. Raymond
An accurate quantification of global methane sources and sinks is imperative for assessing realistic pathways to mitigate climate change. A key challenge of quantifying the Global Methane Budget (Saunois et al., 2020, https://doi.org/10.5194/essd-12-1561-2020) is the lack of consistency in uncertainties between sectors. Here we provide a new perspective on bottom-up (BU) and top-down (TD) methane uncertainties by using an expert opinion analysis based on a questionnaire conducted in 2021. Expectedly, experts rank highest uncertainty and lowest confidence levels in the Global Methane Budget related to natural sources in BU budgets. Here, we further reveal specific uncertainty types and introduce a ranking system for uncertainties in each sector. We find that natural source uncertainty is related particularly to driver data uncertainty in freshwater, vegetation, and coastal/ocean sources, as well as parameter uncertainty in wetland models. Reducing uncertainties, most notably in aquatic and wetland sources will help balance future BU and TD global methane budgets. We suggest a new methane source partitioning over gradients of human disturbance and demonstrate that 76.3% (75.8%–79.4%) or 561 (443–700) Tg CH4 yr−1 of global emissions can be attributed to moderately impacted, man-made, artificial, or fully anthropogenic sources and 23.7% (20.6%–24.2%) or 174 (115–223) Tg CH4 yr−1 to natural and low impacted methane sources. Finally, we identify current research gaps and provide a plan of action to reduce current uncertainties in the Global Methane Budget.
{"title":"Revisiting the Global Methane Cycle Through Expert Opinion","authors":"Judith A. Rosentreter, Lewis Alcott, Taylor Maavara, Xin Sun, Yong Zhou, Noah J. Planavsky, Peter A. Raymond","doi":"10.1029/2023EF004234","DOIUrl":"https://doi.org/10.1029/2023EF004234","url":null,"abstract":"<p>An accurate quantification of global methane sources and sinks is imperative for assessing realistic pathways to mitigate climate change. A key challenge of quantifying the Global Methane Budget (Saunois et al., 2020, https://doi.org/10.5194/essd-12-1561-2020) is the lack of consistency in uncertainties between sectors. Here we provide a new perspective on bottom-up (BU) and top-down (TD) methane uncertainties by using an expert opinion analysis based on a questionnaire conducted in 2021. Expectedly, experts rank highest uncertainty and lowest confidence levels in the Global Methane Budget related to natural sources in BU budgets. Here, we further reveal specific uncertainty types and introduce a ranking system for uncertainties in each sector. We find that natural source uncertainty is related particularly to driver data uncertainty in freshwater, vegetation, and coastal/ocean sources, as well as parameter uncertainty in wetland models. Reducing uncertainties, most notably in aquatic and wetland sources will help balance future BU and TD global methane budgets. We suggest a new methane source partitioning over gradients of human disturbance and demonstrate that 76.3% (75.8%–79.4%) or 561 (443–700) Tg CH<sub>4</sub> yr<sup>−1</sup> of global emissions can be attributed to moderately impacted, man-made, artificial, or fully anthropogenic sources and 23.7% (20.6%–24.2%) or 174 (115–223) Tg CH<sub>4</sub> yr<sup>−1</sup> to natural and low impacted methane sources. Finally, we identify current research gaps and provide a plan of action to reduce current uncertainties in the Global Methane Budget.</p>","PeriodicalId":48748,"journal":{"name":"Earths Future","volume":null,"pages":null},"PeriodicalIF":7.3,"publicationDate":"2024-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023EF004234","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141441332","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}
Miraj B. Kayastha, Chenfu Huang, Jiali Wang, Yun Qian, Zhao Yang, TC Chakraborty, William J. Pringle, Robert D. Hetland, Pengfei Xue
Lake-effect snow (LES) storms, characterized by heavy convective precipitation downwind of large lakes, pose significant coastal hazards with severe socioeconomic consequences in vulnerable areas. In this study, we investigate how devastating LES storms could evolve in the future by employing a storyline approach, using the LES storm that occurred over Buffalo, New York, in November 2022 as an example. Using a Pseudo-Global Warming method with a fully three-dimensional two-way coupled lake-land-atmosphere modeling system at a cloud-resolving 4 km resolution, we show a 14% increase in storm precipitation under the end-century warming. This increase in precipitation is accompanied by a transition in the precipitation form from predominantly snowfall to nearly equal parts snowfall and rainfall. Through additional simulations with isolated atmospheric and lake warming, we discerned that the warmer lake contributes to increased storm precipitation through enhanced evaporation while the warmer atmosphere contributes to the increase in the storm's rainfall, at the expense of snowfall. More importantly, this shift from snowfall to rainfall was found to nearly double the area experiencing another winter hazard, Rain-on-Snow. Our study provides a plausible future storyline for the Buffalo LES storm, focusing on understanding the intricate interplay between atmospheric and lake warming in shaping the future dynamics of LES storms. It emphasizes the importance of accurately capturing the changing lake-atmosphere dynamics during LES storms under future warming.
湖泊效应暴风雪(LES)的特点是在大型湖泊的下风向出现强对流降水,对沿海地区造成重大危害,给脆弱地区带来严重的社会经济后果。在本研究中,我们以 2022 年 11 月发生在纽约布法罗上空的湖效雪风暴为例,采用故事情节法研究了破坏性湖效雪风暴在未来可能如何演变。我们采用伪全球变暖方法,在云分辨率为 4 千米的全三维双向耦合湖泊-陆地-大气建模系统中显示,在本世纪末气候变暖的情况下,风暴降水量将增加 14%。降水量增加的同时,降水形式也从以降雪为主转变为降雪和降雨几乎各占一半。通过对大气和湖泊单独变暖的额外模拟,我们发现,变暖的湖泊通过增强蒸发促进了风暴降水量的增加,而变暖的大气则以降雪为代价促进了风暴降水量的增加。更重要的是,从降雪到降雨的这种转变几乎使遭遇另一种冬季灾害--"雪中雨 "的面积增加了一倍。我们的研究为水牛城 LES 风暴提供了一个可信的未来故事情节,重点是了解大气和湖泊变暖在塑造 LES 风暴未来动态方面错综复杂的相互作用。它强调了在未来气候变暖的情况下准确捕捉 LES 风暴期间湖泊-大气动态变化的重要性。
{"title":"How Could Future Climate Conditions Reshape a Devastating Lake-Effect Snow Storm?","authors":"Miraj B. Kayastha, Chenfu Huang, Jiali Wang, Yun Qian, Zhao Yang, TC Chakraborty, William J. Pringle, Robert D. Hetland, Pengfei Xue","doi":"10.1029/2024EF004622","DOIUrl":"https://doi.org/10.1029/2024EF004622","url":null,"abstract":"<p>Lake-effect snow (LES) storms, characterized by heavy convective precipitation downwind of large lakes, pose significant coastal hazards with severe socioeconomic consequences in vulnerable areas. In this study, we investigate how devastating LES storms could evolve in the future by employing a storyline approach, using the LES storm that occurred over Buffalo, New York, in November 2022 as an example. Using a Pseudo-Global Warming method with a fully three-dimensional two-way coupled lake-land-atmosphere modeling system at a cloud-resolving 4 km resolution, we show a 14% increase in storm precipitation under the end-century warming. This increase in precipitation is accompanied by a transition in the precipitation form from predominantly snowfall to nearly equal parts snowfall and rainfall. Through additional simulations with isolated atmospheric and lake warming, we discerned that the warmer lake contributes to increased storm precipitation through enhanced evaporation while the warmer atmosphere contributes to the increase in the storm's rainfall, at the expense of snowfall. More importantly, this shift from snowfall to rainfall was found to nearly double the area experiencing another winter hazard, Rain-on-Snow. Our study provides a plausible future storyline for the Buffalo LES storm, focusing on understanding the intricate interplay between atmospheric and lake warming in shaping the future dynamics of LES storms. It emphasizes the importance of accurately capturing the changing lake-atmosphere dynamics during LES storms under future warming.</p>","PeriodicalId":48748,"journal":{"name":"Earths Future","volume":null,"pages":null},"PeriodicalIF":7.3,"publicationDate":"2024-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024EF004622","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141441331","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}
Mike C. Rowley, Nicola Falco, Elaine Pegoraro, Baptiste Dafflon, Cynthia Gerlein-Safdi, Yuxin Wu, Cristina Castanha, Jasquelin Peña, Peter S. Nico, Margaret S. Torn
Grasslands are one of the most common land-cover types, providing important ecosystem services globally, yet few studies have examined grassland critical-zone functioning throughout hillslopes. This study characterised a coastal grassland over a small hillslope at Point Reyes National Seashore, California, using multidisciplinary techniques, combining remotely-sensed, geophysical, plant, and soil measurements. Clustering techniques delineated the study area into four landscape zones, up-, mid-, and down-slope, and a bordering riparian ecotone, which had distinct environmental properties that varied spatially across the site, with depth, and time. Soil moisture increased with depth and down slope towards a bordering riparian zone, and co-varied with soil CO2 flux rates both spatially and temporally. This highlighted three distinct controls of soil moisture on soil respiration: CO2 fluxes were inhibited by high moisture content in the down-slope during the wet winter months, and converged across landscape positions in the dry summer months, while also displaying post-rain pulses. The normalised difference vegetation index (NDVI) ranged from 0.32 (September)–0.80 (April) and correlated positively with soil moisture and aboveground biomass, moving down slope. Yet, NDVI, aboveground biomass, and soil moisture were not correlated to soil organic carbon (SOC) content (0.4%–4.5%), which was highest in the mid-slope. The SOC content may instead be linked to shifts in dominant grassland species and their rhizosphere properties with landscape position. This multidisciplinary characterisation highlighted significant heterogeneity in grassland properties with landscape position, and demonstrated an approach that could be used to characterise other critical-zone environments on hillslopes.
{"title":"The Importance of Accounting for Landscape Position When Investigating Grasslands: A Multidisciplinary Characterisation of a California Coastal Grassland","authors":"Mike C. Rowley, Nicola Falco, Elaine Pegoraro, Baptiste Dafflon, Cynthia Gerlein-Safdi, Yuxin Wu, Cristina Castanha, Jasquelin Peña, Peter S. Nico, Margaret S. Torn","doi":"10.1029/2023EF004208","DOIUrl":"https://doi.org/10.1029/2023EF004208","url":null,"abstract":"<p>Grasslands are one of the most common land-cover types, providing important ecosystem services globally, yet few studies have examined grassland critical-zone functioning throughout hillslopes. This study characterised a coastal grassland over a small hillslope at Point Reyes National Seashore, California, using multidisciplinary techniques, combining remotely-sensed, geophysical, plant, and soil measurements. Clustering techniques delineated the study area into four landscape zones, up-, mid-, and down-slope, and a bordering riparian ecotone, which had distinct environmental properties that varied spatially across the site, with depth, and time. Soil moisture increased with depth and down slope towards a bordering riparian zone, and co-varied with soil CO<sub>2</sub> flux rates both spatially and temporally. This highlighted three distinct controls of soil moisture on soil respiration: CO<sub>2</sub> fluxes were inhibited by high moisture content in the down-slope during the wet winter months, and converged across landscape positions in the dry summer months, while also displaying post-rain pulses. The normalised difference vegetation index (NDVI) ranged from 0.32 (September)–0.80 (April) and correlated positively with soil moisture and aboveground biomass, moving down slope. Yet, NDVI, aboveground biomass, and soil moisture were not correlated to soil organic carbon (SOC) content (0.4%–4.5%), which was highest in the mid-slope. The SOC content may instead be linked to shifts in dominant grassland species and their rhizosphere properties with landscape position. This multidisciplinary characterisation highlighted significant heterogeneity in grassland properties with landscape position, and demonstrated an approach that could be used to characterise other critical-zone environments on hillslopes.</p>","PeriodicalId":48748,"journal":{"name":"Earths Future","volume":null,"pages":null},"PeriodicalIF":7.3,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023EF004208","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141439621","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}
Charlotte Connolly, Emily Prewett, Elizabeth A. Barnes, James W. Hurrell
Earth system models are powerful tools to simulate the climate response to hypothetical climate intervention strategies, such as stratospheric aerosol injection (SAI). Recent simulations of SAI implement a tool from control theory, called a controller, to determine the quantity of aerosol to inject into the stratosphere to reach or maintain specified global temperature targets, such as limiting global warming to 1.5°C above pre-industrial temperatures. This work explores how internal (unforced) climate variability can impact controller-determined injection amounts using the Assessing Responses and Impacts of Solar climate intervention on the Earth system with Stratospheric Aerosol Injection (ARISE-SAI) simulations. Since the ARISE-SAI controller determines injection amounts by comparing global annual-mean surface temperature to predetermined temperature targets, internal variability that impacts temperature can impact the total injection amount as well. Using an offline version of the ARISE-SAI controller and data from Earth system model simulations, we quantify how internal climate variability and volcanic eruptions impact injection amounts. While idealized, this approach allows for the investigation of a large variety of climate states without additional simulations and can be used to attribute controller sensitivities to specific modes of internal variability.
地球系统模型是模拟气候对假设的气候干预策略(如平流层气溶胶注入(SAI))反应的有力工具。最近对 SAI 的模拟采用了控制理论中的一种工具,即控制器,来确定向平流层注入气溶胶的数量,以达到或维持指定的全球温度目标,例如将全球升温限制在比工业化前温度高 1.5°C 的范围内。这项研究利用 "评估太阳气候干预对地球系统的响应和影响与平流层气溶胶注入"(ARISE-SAI)模拟,探讨了内部(非强迫性)气候变异如何影响控制器确定的注入量。由于 ARISE-SAI 控制器是通过比较全球年平均表面温度和预定温度目标来确定注入量的,因此影响温度的内部变化也会影响总注入量。利用离线版 ARISE-SAI 控制器和地球系统模型模拟数据,我们量化了内部气候变异和火山爆发对注入量的影响。这种方法虽然是理想化的,但可以在不进行额外模拟的情况下对多种气候状态进行研究,并可用于确定控制器对特定内部变异模式的敏感性。
{"title":"Quantifying the Impact of Internal Variability on the CESM2 Control Algorithm for Stratospheric Aerosol Injection","authors":"Charlotte Connolly, Emily Prewett, Elizabeth A. Barnes, James W. Hurrell","doi":"10.1029/2023EF004300","DOIUrl":"https://doi.org/10.1029/2023EF004300","url":null,"abstract":"<p>Earth system models are powerful tools to simulate the climate response to hypothetical climate intervention strategies, such as stratospheric aerosol injection (SAI). Recent simulations of SAI implement a tool from control theory, called a controller, to determine the quantity of aerosol to inject into the stratosphere to reach or maintain specified global temperature targets, such as limiting global warming to 1.5°C above pre-industrial temperatures. This work explores how internal (unforced) climate variability can impact controller-determined injection amounts using the Assessing Responses and Impacts of Solar climate intervention on the Earth system with Stratospheric Aerosol Injection (ARISE-SAI) simulations. Since the ARISE-SAI controller determines injection amounts by comparing global annual-mean surface temperature to predetermined temperature targets, internal variability that impacts temperature can impact the total injection amount as well. Using an offline version of the ARISE-SAI controller and data from Earth system model simulations, we quantify how internal climate variability and volcanic eruptions impact injection amounts. While idealized, this approach allows for the investigation of a large variety of climate states without additional simulations and can be used to attribute controller sensitivities to specific modes of internal variability.</p>","PeriodicalId":48748,"journal":{"name":"Earths Future","volume":null,"pages":null},"PeriodicalIF":7.3,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023EF004300","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141435672","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}
Yongyong Zhang, Yongqiang Zhang, Xiaoyan Zhai, Jun Xia, Qiuhong Tang, Tongtiegang Zhao, Wei Wang
Predicting flood event classes aids in the comprehensive investigation of flood behavior dynamics and supports flood early warning and emergency plan development. Existing studies have mainly focused on historical flood event classification and the prediction of flood hydrographs or certain metrics (e.g., magnitude and timing) but have not focused on predicting flood event classes. Our study proposes a new approach for predicting flood event classes based on the class membership functions of flood regime metrics and hydrological modeling. The approach is validated using 1446 unimpacted flood events in 68 headstream catchments widely distributed across China. The new approach performs well, with class hit rates of 68.3% ± 0.4% for all events; 65.8% ± 0.6%, 56.8% ± 0.9%, and 69.5% ± 0.9% for the small, moderate and high spike flood event classes, respectively; and 82.5% ± 1.2% and 75.4% ± 1.1% for the moderate and high dumpy flood event classes, respectively. Furthermore, it performs better in the basins of northern China than in those of southern China, particularly for the small spike flood event class in the Songliao and Yellow River Basins, with hit rates of 80.0% ± 3.2% and 78.8% ± 3.2%, respectively. Our results indicate that the new approach will help improve the prediction performance of flood events and their corresponding classes, and provide deep insights into the comprehensive dynamic patterns of flood events for early warning and control management.
{"title":"Predicting Flood Event Class Using a Novel Class Membership Function and Hydrological Modeling","authors":"Yongyong Zhang, Yongqiang Zhang, Xiaoyan Zhai, Jun Xia, Qiuhong Tang, Tongtiegang Zhao, Wei Wang","doi":"10.1029/2023EF004081","DOIUrl":"https://doi.org/10.1029/2023EF004081","url":null,"abstract":"<p>Predicting flood event classes aids in the comprehensive investigation of flood behavior dynamics and supports flood early warning and emergency plan development. Existing studies have mainly focused on historical flood event classification and the prediction of flood hydrographs or certain metrics (e.g., magnitude and timing) but have not focused on predicting flood event classes. Our study proposes a new approach for predicting flood event classes based on the class membership functions of flood regime metrics and hydrological modeling. The approach is validated using 1446 unimpacted flood events in 68 headstream catchments widely distributed across China. The new approach performs well, with class hit rates of 68.3% ± 0.4% for all events; 65.8% ± 0.6%, 56.8% ± 0.9%, and 69.5% ± 0.9% for the small, moderate and high spike flood event classes, respectively; and 82.5% ± 1.2% and 75.4% ± 1.1% for the moderate and high dumpy flood event classes, respectively. Furthermore, it performs better in the basins of northern China than in those of southern China, particularly for the small spike flood event class in the Songliao and Yellow River Basins, with hit rates of 80.0% ± 3.2% and 78.8% ± 3.2%, respectively. Our results indicate that the new approach will help improve the prediction performance of flood events and their corresponding classes, and provide deep insights into the comprehensive dynamic patterns of flood events for early warning and control management.</p>","PeriodicalId":48748,"journal":{"name":"Earths Future","volume":null,"pages":null},"PeriodicalIF":7.3,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023EF004081","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141435673","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}
Tropical cyclones are often accompanied by large amount of precipitation potentially impacting stream hydrochemistry. Global warming is altering typhoon disturbance regime. Little is known about how cyclone changes, especially cyclone-frequency reduction may affect stream hydrochemistry. In this study, we compared water and nutrient input via precipitation and output via streamflow between a frequent-typhoon period (2013–2017), with 1.2 typhoon yr−1, and a no-typhoon period (2018–2022) at a long-term monitoring site, the Fushan Experimental Forest of Taiwan. Precipitation and streamflow quantities were not different between the two periods because typhoons increased the fluctuation but not the mean of monthly precipitation in the major typhoon months (July–September). Inputs of Mg2+, NO3−, and SO42− via precipitation were greater in the frequent-typhoon period than the no-typhoon period while inputs of other ions were not different between the two periods. Only the output of Mg2+ was different between the two periods, greater in the frequent-typhoon period. Output/input ratio of NO3− was greater in the no-typhoon period than the frequent-typhoon period despite the greater input in the frequent-typhoon period, while no differences were found for others. Increases in mineralization rates due to warming is suggested to be the cause of the greater NO3− output/input ratio during the no-typhoon period. Relationships between stream discharge and ion export were similar between the two periods both with and without removing typhoon events. The limited variation in hydrochemistry between periods of contrasting cyclone activities suggests high resilience of the undisturbed subtropical forests to changes in cyclone frequency at the decadal scale.
{"title":"The Limited Effect of Reduced Typhoon Frequency on Stream Hydrochemistry in a Subtropical Forest Watershed","authors":"Chung-Te Chang, Jr-Chuan Huang, Lixin Wang, Hsiang-Hua Wang, Jun-Yi Lee, Teng-Chiu Lin","doi":"10.1029/2023EF004056","DOIUrl":"https://doi.org/10.1029/2023EF004056","url":null,"abstract":"<p>Tropical cyclones are often accompanied by large amount of precipitation potentially impacting stream hydrochemistry. Global warming is altering typhoon disturbance regime. Little is known about how cyclone changes, especially cyclone-frequency reduction may affect stream hydrochemistry. In this study, we compared water and nutrient input via precipitation and output via streamflow between a frequent-typhoon period (2013–2017), with 1.2 typhoon yr<sup>−1</sup>, and a no-typhoon period (2018–2022) at a long-term monitoring site, the Fushan Experimental Forest of Taiwan. Precipitation and streamflow quantities were not different between the two periods because typhoons increased the fluctuation but not the mean of monthly precipitation in the major typhoon months (July–September). Inputs of Mg<sup>2+</sup>, NO<sub>3</sub><sup>−</sup>, and SO<sub>4</sub><sup>2−</sup> via precipitation were greater in the frequent-typhoon period than the no-typhoon period while inputs of other ions were not different between the two periods. Only the output of Mg<sup>2+</sup> was different between the two periods, greater in the frequent-typhoon period. Output/input ratio of NO<sub>3</sub><sup>−</sup> was greater in the no-typhoon period than the frequent-typhoon period despite the greater input in the frequent-typhoon period, while no differences were found for others. Increases in mineralization rates due to warming is suggested to be the cause of the greater NO<sub>3</sub><sup>−</sup> output/input ratio during the no-typhoon period. Relationships between stream discharge and ion export were similar between the two periods both with and without removing typhoon events. The limited variation in hydrochemistry between periods of contrasting cyclone activities suggests high resilience of the undisturbed subtropical forests to changes in cyclone frequency at the decadal scale.</p>","PeriodicalId":48748,"journal":{"name":"Earths Future","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023EF004056","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141425049","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}
Z. Y. Hu, Q. H. Dai, Y. J. Yan, Y. Zhang, H. Y. Li, H. Zhou, Y. W. Yao
Ecosystem water use efficiency (WUE) is a crucial parameter for understanding the interaction between carbon and water cycles. However, the spatio–temporal evolution and drivers of WUE remain unclear. This study utilized global annual scale global land surface satellite gross primary productivity and evapotranspiration data from 1982 to 2018 to estimate WUE and analyze its spatio–temporal characteristics. Additionally, the study investigated the response of WUE changes to five environmental factors (precipitation [PRE], soil moisture, temperature [TEM], palmer drought severity index, and vapor pressure deficit [VPD]) on WUE changes using partial correlation and structural equation modeling. The results suggested that the global annual WUE increased markedly over the study period, at an average rate of 0.0016 gC m−2 mm−1 H2O year−1. In contrast to the existing knowledge on the drivers of WUE change, climate change was found to have a larger contribution to WUE changes at the global and regional scales, especially in terms of TEM and VPD. A positive correlation between TEM and WUE was observed, but extreme TEM could lead to a decrease in WUE. VPD had the most significant direct effect on WUE, and its negative effect offset the positive influence of TEM especially in hyper-arid, semi-arid, and arid regions. These findings offer new insights into the impact of VPD and global warming on WUE.
{"title":"Dissecting the Characteristics and Driver Factors on Global Water Use Efficiency Using GLASS Data Sets","authors":"Z. Y. Hu, Q. H. Dai, Y. J. Yan, Y. Zhang, H. Y. Li, H. Zhou, Y. W. Yao","doi":"10.1029/2024EF004630","DOIUrl":"https://doi.org/10.1029/2024EF004630","url":null,"abstract":"<p>Ecosystem water use efficiency (WUE) is a crucial parameter for understanding the interaction between carbon and water cycles. However, the spatio–temporal evolution and drivers of WUE remain unclear. This study utilized global annual scale global land surface satellite gross primary productivity and evapotranspiration data from 1982 to 2018 to estimate WUE and analyze its spatio–temporal characteristics. Additionally, the study investigated the response of WUE changes to five environmental factors (precipitation [PRE], soil moisture, temperature [TEM], palmer drought severity index, and vapor pressure deficit [VPD]) on WUE changes using partial correlation and structural equation modeling. The results suggested that the global annual WUE increased markedly over the study period, at an average rate of 0.0016 gC m<sup>−2</sup> mm<sup>−1</sup> H<sub>2</sub>O year<sup>−1</sup>. In contrast to the existing knowledge on the drivers of WUE change, climate change was found to have a larger contribution to WUE changes at the global and regional scales, especially in terms of TEM and VPD. A positive correlation between TEM and WUE was observed, but extreme TEM could lead to a decrease in WUE. VPD had the most significant direct effect on WUE, and its negative effect offset the positive influence of TEM especially in hyper-arid, semi-arid, and arid regions. These findings offer new insights into the impact of VPD and global warming on WUE.</p>","PeriodicalId":48748,"journal":{"name":"Earths Future","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024EF004630","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141425051","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}
Henry Ssembatya, Jordan D. Kern, Konstantinos Oikonomou, Nathalie Voisin, Casey D. Burleyson, Kerem Ziya Akdemir
Around 60% of households in Texas currently rely on electricity for space heating. As decarbonization efforts increase, non-electrified households could adopt electric heat pumps, significantly increasing peak (highest) electricity demand in winter. Simultaneously, anthropogenic climate change is expected to increase temperatures, the potential for summer heat waves, and associated electricity demand for cooling. Uncertainty regarding the timing and magnitude of these concurrent changes raises questions about how they will jointly affect the seasonality of peak demand, firm capacity requirements, and grid reliability. This study investigates the net effects of residential space heating electrification and climate change on long-term demand patterns and load shedding potential, using climate change projections, a predictive load model, and a direct current optimal power flow (DCOPF) model of the Texas grid. Results show that full electrification of residential space heating by replacing existing fossil fuel use with higher efficiency heat pumps could significantly improve reliability under hotter futures. Less efficient heat pumps may result in more severe winter peaking events and increased reliability risks. As heating electrification intensifies, system planners will need to balance the potential for greater resource adequacy risk caused by shifts in seasonal peaking behavior alongside the benefits (improved efficiency and reductions in emissions).
{"title":"Dual Impacts of Space Heating Electrification and Climate Change Increase Uncertainties in Peak Load Behavior and Grid Capacity Requirements in Texas","authors":"Henry Ssembatya, Jordan D. Kern, Konstantinos Oikonomou, Nathalie Voisin, Casey D. Burleyson, Kerem Ziya Akdemir","doi":"10.1029/2024EF004443","DOIUrl":"https://doi.org/10.1029/2024EF004443","url":null,"abstract":"<p>Around 60% of households in Texas currently rely on electricity for space heating. As decarbonization efforts increase, non-electrified households could adopt electric heat pumps, significantly increasing peak (highest) electricity demand in winter. Simultaneously, anthropogenic climate change is expected to increase temperatures, the potential for summer heat waves, and associated electricity demand for cooling. Uncertainty regarding the timing and magnitude of these concurrent changes raises questions about how they will jointly affect the seasonality of peak demand, firm capacity requirements, and grid reliability. This study investigates the net effects of residential space heating electrification and climate change on long-term demand patterns and load shedding potential, using climate change projections, a predictive load model, and a direct current optimal power flow (DCOPF) model of the Texas grid. Results show that full electrification of residential space heating by replacing existing fossil fuel use with higher efficiency heat pumps could significantly improve reliability under hotter futures. Less efficient heat pumps may result in more severe winter peaking events and increased reliability risks. As heating electrification intensifies, system planners will need to balance the potential for greater resource adequacy risk caused by shifts in seasonal peaking behavior alongside the benefits (improved efficiency and reductions in emissions).</p>","PeriodicalId":48748,"journal":{"name":"Earths Future","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024EF004443","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141425050","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}
Stratospheric aerosol injection (SAI) has been proposed as a potential method for mitigating risks and impacts associated with anthropogenic climate change. One such risk is widespread permafrost thaw and associated carbon release. While permafrost has been shown to stabilize under different SAI scenarios, natural variability may mask this forced response and make it difficult to detect if and when SAI is stabilizing permafrost. Here we use the 10-member ensemble from the ARISE-SAI-1.5 simulations to assess the spread in projected active layer depth and permafrost temperature across boreal permafrost soils and specifically in four peatland and Yedoma regions. The forced response in active layer depth and permafrost temperature quickly diverges between an SAI and non-SAI world, but individual ensemble members overlap for several years following SAI deployment. We find that, due to projected permafrost variability, it may take more than a decade of SAI deployment to detect the effects of SAI on permafrost temperature and almost 30 years to detect its effects on active layer depth. Not only does natural variability make it more difficult to detect SAI's influence, it could also affect the likelihood of reaching a permafrost tipping point. In some realizations, SAI fails to prevent a local tipping point that is also reached in a non-SAI world. Our results underscore the importance of accounting for natural variability in assessments of SAI's potential influence on the climate system.
平流层气溶胶注入(SAI)被认为是减轻与人为气候变化相关的风险和影响的一种潜在方法。其中一个风险是大面积的永久冻土融化和相关的碳释放。虽然在不同的 SAI 情景下,永久冻土已被证明趋于稳定,但自然变异可能会掩盖这种被迫反应,从而难以检测 SAI 是否以及何时使永久冻土趋于稳定。在这里,我们使用 ARISE-SAI-1.5 模拟的 10 个成员集合来评估整个北方冻土带,特别是四个泥炭地和叶多玛地区的预计活动层深度和冻土温度的分布。在 SAI 和非 SAI 世界中,活动层深度和冻土温度的强迫响应很快就会出现分歧,但在 SAI 部署后的几年中,各个集合成员会出现重叠。我们发现,由于预计的永久冻土变异性,可能需要部署 SAI 十多年才能检测到 SAI 对永久冻土温度的影响,需要近 30 年才能检测到 SAI 对活动层深度的影响。自然变化不仅会增加检测 SAI 影响的难度,还会影响达到冻土临界点的可能性。在某些情况下,SAI 无法阻止局部临界点的出现,而在非 SAI 的世界中,该临界点也会出现。我们的研究结果强调了在评估 SAI 对气候系统的潜在影响时考虑自然变异的重要性。
{"title":"Natural Variability Can Mask Forced Permafrost Response to Stratospheric Aerosol Injection in the ARISE-SAI-1.5 Simulations","authors":"A. L. Morrison, E. A. Barnes, J. W. Hurrell","doi":"10.1029/2023EF004191","DOIUrl":"https://doi.org/10.1029/2023EF004191","url":null,"abstract":"<p>Stratospheric aerosol injection (SAI) has been proposed as a potential method for mitigating risks and impacts associated with anthropogenic climate change. One such risk is widespread permafrost thaw and associated carbon release. While permafrost has been shown to stabilize under different SAI scenarios, natural variability may mask this forced response and make it difficult to detect if and when SAI is stabilizing permafrost. Here we use the 10-member ensemble from the ARISE-SAI-1.5 simulations to assess the spread in projected active layer depth and permafrost temperature across boreal permafrost soils and specifically in four peatland and Yedoma regions. The forced response in active layer depth and permafrost temperature quickly diverges between an SAI and non-SAI world, but individual ensemble members overlap for several years following SAI deployment. We find that, due to projected permafrost variability, it may take more than a decade of SAI deployment to detect the effects of SAI on permafrost temperature and almost 30 years to detect its effects on active layer depth. Not only does natural variability make it more difficult to detect SAI's influence, it could also affect the likelihood of reaching a permafrost tipping point. In some realizations, SAI fails to prevent a local tipping point that is also reached in a non-SAI world. Our results underscore the importance of accounting for natural variability in assessments of SAI's potential influence on the climate system.</p>","PeriodicalId":48748,"journal":{"name":"Earths Future","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023EF004191","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141424900","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}
Seok-Geun Oh, Seok-Woo Son, Sujong Jeong, Yang-Ki Cho
Marine heatwave (MHW), a prolonged period of anomalously warm seawater, has a catastrophic repercussion on marine ecosystems. With global warming, MHWs have become increasingly frequent, intense, and prolonged. To avoid irreversible damages from such extreme events, net-zero carbon emissions by the 2050s, called carbon neutrality, were proposed. Here, we evaluate the impact of carbon neutrality on MHWs in the late 21st century using multi-model projections from the Coupled Model Intercomparison Project Phase 6 (CMIP6) Shared Socioeconomic Pathway (SSP) 1–1.9 and SSP3-7.0 scenarios. It is found that if the current regional rivalry over carbon emissions continues (i.e., SSP3-7.0), the MHWs in the late 21st century will become stronger and longer than historical ones, especially in the western boundary current and equatorial current regions. Approximately 68% of the global ocean will be exposed to permanent MHWs, regionally 93% in the Indian Ocean, 76% in the Pacific Ocean, 68% in the Atlantic Ocean, 65% in the Coastal Ocean, and 48% in the Southern Ocean. Such MHWs can be significantly reduced by achieving carbon neutrality (i.e., SSP1-1.9). In particular, the spatial proportion of the ocean exposed to permanent MHWs can be reduced to as low as 0.02%–0.07%, depending on the regions. This result underscores the critical importance of ongoing efforts to achieve net-zero carbon emissions to reduce the potential ecological risks induced by extreme MHWs.
{"title":"Significant Reduction of Potential Exposure to Extreme Marine Heatwaves by Achieving Carbon Neutrality","authors":"Seok-Geun Oh, Seok-Woo Son, Sujong Jeong, Yang-Ki Cho","doi":"10.1029/2024EF004420","DOIUrl":"https://doi.org/10.1029/2024EF004420","url":null,"abstract":"<p>Marine heatwave (MHW), a prolonged period of anomalously warm seawater, has a catastrophic repercussion on marine ecosystems. With global warming, MHWs have become increasingly frequent, intense, and prolonged. To avoid irreversible damages from such extreme events, net-zero carbon emissions by the 2050s, called carbon neutrality, were proposed. Here, we evaluate the impact of carbon neutrality on MHWs in the late 21st century using multi-model projections from the Coupled Model Intercomparison Project Phase 6 (CMIP6) Shared Socioeconomic Pathway (SSP) 1–1.9 and SSP3-7.0 scenarios. It is found that if the current regional rivalry over carbon emissions continues (i.e., SSP3-7.0), the MHWs in the late 21st century will become stronger and longer than historical ones, especially in the western boundary current and equatorial current regions. Approximately 68% of the global ocean will be exposed to permanent MHWs, regionally 93% in the Indian Ocean, 76% in the Pacific Ocean, 68% in the Atlantic Ocean, 65% in the Coastal Ocean, and 48% in the Southern Ocean. Such MHWs can be significantly reduced by achieving carbon neutrality (i.e., SSP1-1.9). In particular, the spatial proportion of the ocean exposed to permanent MHWs can be reduced to as low as 0.02%–0.07%, depending on the regions. This result underscores the critical importance of ongoing efforts to achieve net-zero carbon emissions to reduce the potential ecological risks induced by extreme MHWs.</p>","PeriodicalId":48748,"journal":{"name":"Earths Future","volume":null,"pages":null},"PeriodicalIF":8.2,"publicationDate":"2024-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024EF004420","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141329369","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}