Pub Date : 2025-01-01Epub Date: 2025-08-26DOI: 10.1007/s44195-025-00112-x
Ya-Sin Yang, Hsin-Fu Yeh, Chia-Chi Huang, Jonathan D Mackay, John P Bloomfield, Kuo-Chin Hsu, Shien-Tsung Chen
Given the pressures on water resources caused by global climate change and human activities, the assessment and management of groundwater resources in mountainous region have become increasingly important. The central mountainous region of Taiwan, as one of the significant sources of groundwater recharge, plays a critical role in overall water resource management due to its groundwater storage capacity and recharge capability. Addressing the challenges of limited survey and observational data in mountainous groundwater assessments, this study uses the lumped parameter groundwater model AquiMod to analyze long-term groundwater level changes at 23 monitoring stations in mountainous areas of central Taiwan. This study is based on long-term groundwater level monitoring data (2010-2021) analyzing the relationship between groundwater levels and precipitation, and performs model calibration and prediction. The results indicate a strong correlation between groundwater levels in mountainous areas and precipitation. While the model predictions were satisfactory for most monitoring stations, obtaining Nash Sutcliffe efficiency scores of between 0.5 and 0.9 at 14 of the 23 monitoring stations. However, poorer performance at several stations reflects limitations arising from data gaps, complex local geology, and the inability of the lumped model to represent lateral recharge or anthropogenic influences. Model sensitivity analysis further highlights the critical role of unsaturated zone parameters, such as rooting depth, soil storage and upper-layer saturated hydraulic conductivity, in shaping groundwater responses. In summary, the lumped parameter groundwater model has proven practical for evaluating groundwater in Taiwan's mountainous regions and can serve as a reference for the sustainable management of future water resources.
{"title":"Assessing groundwater dynamics in data-scarce mountainous regions using a lumped parameter groundwater model.","authors":"Ya-Sin Yang, Hsin-Fu Yeh, Chia-Chi Huang, Jonathan D Mackay, John P Bloomfield, Kuo-Chin Hsu, Shien-Tsung Chen","doi":"10.1007/s44195-025-00112-x","DOIUrl":"10.1007/s44195-025-00112-x","url":null,"abstract":"<p><p>Given the pressures on water resources caused by global climate change and human activities, the assessment and management of groundwater resources in mountainous region have become increasingly important. The central mountainous region of Taiwan, as one of the significant sources of groundwater recharge, plays a critical role in overall water resource management due to its groundwater storage capacity and recharge capability. Addressing the challenges of limited survey and observational data in mountainous groundwater assessments, this study uses the lumped parameter groundwater model AquiMod to analyze long-term groundwater level changes at 23 monitoring stations in mountainous areas of central Taiwan. This study is based on long-term groundwater level monitoring data (2010-2021) analyzing the relationship between groundwater levels and precipitation, and performs model calibration and prediction. The results indicate a strong correlation between groundwater levels in mountainous areas and precipitation. While the model predictions were satisfactory for most monitoring stations, obtaining Nash Sutcliffe efficiency scores of between 0.5 and 0.9 at 14 of the 23 monitoring stations. However, poorer performance at several stations reflects limitations arising from data gaps, complex local geology, and the inability of the lumped model to represent lateral recharge or anthropogenic influences. Model sensitivity analysis further highlights the critical role of unsaturated zone parameters, such as rooting depth, soil storage and upper-layer saturated hydraulic conductivity, in shaping groundwater responses. In summary, the lumped parameter groundwater model has proven practical for evaluating groundwater in Taiwan's mountainous regions and can serve as a reference for the sustainable management of future water resources.</p>","PeriodicalId":22259,"journal":{"name":"Terrestrial, Atmospheric and Oceanic Sciences","volume":"36 1","pages":"28"},"PeriodicalIF":1.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12404314/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144993551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 : 2024-01-02DOI: 10.1007/s44195-023-00059-x
Bor-Shouh Huang, C. Ku, Chin-Jen Lin, Shiann-Jong Lee, Yen-Ling Eileen Chen, Juen-Shi Jiang, Wei-Fang Sun
{"title":"The first 30 min hidden aftershocks of the 2022 September 17, ML 6.4, Guanshan, Taiwan earthquake and its seismological implications","authors":"Bor-Shouh Huang, C. Ku, Chin-Jen Lin, Shiann-Jong Lee, Yen-Ling Eileen Chen, Juen-Shi Jiang, Wei-Fang Sun","doi":"10.1007/s44195-023-00059-x","DOIUrl":"https://doi.org/10.1007/s44195-023-00059-x","url":null,"abstract":"","PeriodicalId":22259,"journal":{"name":"Terrestrial, Atmospheric and Oceanic Sciences","volume":"29 11","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139389798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-01DOI: 10.1007/s44195-023-00056-0
Marco Polo A. Ibañez, Samuel C. Martirez, Alvin G. Pura, Ramjun A. Sajulga, E. Cayanan, Ben Jong-Dao Jou, Wei-Yu Chang
{"title":"Development of quantitative precipitation estimation (QPE) relations for dual-polarization radars based on raindrop size distribution measurements in Metro Manila, Philippines","authors":"Marco Polo A. Ibañez, Samuel C. Martirez, Alvin G. Pura, Ramjun A. Sajulga, E. Cayanan, Ben Jong-Dao Jou, Wei-Yu Chang","doi":"10.1007/s44195-023-00056-0","DOIUrl":"https://doi.org/10.1007/s44195-023-00056-0","url":null,"abstract":"","PeriodicalId":22259,"journal":{"name":"Terrestrial, Atmospheric and Oceanic Sciences","volume":"173 2","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139023050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-01DOI: 10.1007/s44195-023-00057-z
Benjamin M. Yang, Himanshu Mittal, Yih-Min Wu
{"title":"P-Alert earthquake early warning system: case study of the 2022 Chishang earthquake at Taitung, Taiwan","authors":"Benjamin M. Yang, Himanshu Mittal, Yih-Min Wu","doi":"10.1007/s44195-023-00057-z","DOIUrl":"https://doi.org/10.1007/s44195-023-00057-z","url":null,"abstract":"","PeriodicalId":22259,"journal":{"name":"Terrestrial, Atmospheric and Oceanic Sciences","volume":"155 ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139015784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-01DOI: 10.1007/s44195-023-00058-y
F. Widiatmoko, J. Yen, I. Yen, Shao-Yi Huang, Nai-Wun Shih
{"title":"Assessing the Yuli surface deformation from the 20220918 Chishang earthquake: an integrated RTK GNSS network approach","authors":"F. Widiatmoko, J. Yen, I. Yen, Shao-Yi Huang, Nai-Wun Shih","doi":"10.1007/s44195-023-00058-y","DOIUrl":"https://doi.org/10.1007/s44195-023-00058-y","url":null,"abstract":"","PeriodicalId":22259,"journal":{"name":"Terrestrial, Atmospheric and Oceanic Sciences","volume":"8 12","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139015387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-13DOI: 10.1007/s44195-023-00054-2
Jiman Zhang, Xiaohua Xu, Jia Luo
Abstract This study uses the three-cornered hat (3CH) method to estimate the observation error variances (ErrVars) of FY-3C RO refractivity, temperature, and specific humidity for the first time. The FY-3C RO data was compared to the three reference datasets including radiosonde observations and NCEP and ERA-Interim reanalyses. The ErrVars of FY-3C RO data are estimated at 18 globally distributed radiosonde stations by using the three reference datasets and are compared to corresponding gridded ErrVars estimated using only the two model datasets as references. The two types of estimates show good correlations at different heights, while the gridded estimates are generally the smaller ones, which may be attributed to the neglection of error correlations among the datasets when applying the 3CH method. Due to the lack of radiosonde data in oceanic and polar regions, the global distributions of FY-3C RO observation errors are presented based on the estimated 5° × 5° gridded ErrVars. The global distribution of the FY-3C RO fractional error standard deviations (ErrSDs) demonstrates that the observation error varies greatly at different pressure levels and latitudes. Specifically, the refractivity ErrSDs at 200 hPa and 50 hPa are significantly higher around 30°N and 30°S than in other areas. The specific humidity ErrSDs generally increase as pressure levels decrease. In addition, statistics show that the fractional ErrSDs of refractivity are generally the lowest between 45° N–75° N and 45° S–75° S at all pressure levels, and land-sea differences exist in the fractional ErrSDs for all three types of RO data.
{"title":"Estimating the observation errors of FY-3C radio occultation dataset using the three-cornered hat method","authors":"Jiman Zhang, Xiaohua Xu, Jia Luo","doi":"10.1007/s44195-023-00054-2","DOIUrl":"https://doi.org/10.1007/s44195-023-00054-2","url":null,"abstract":"Abstract This study uses the three-cornered hat (3CH) method to estimate the observation error variances (ErrVars) of FY-3C RO refractivity, temperature, and specific humidity for the first time. The FY-3C RO data was compared to the three reference datasets including radiosonde observations and NCEP and ERA-Interim reanalyses. The ErrVars of FY-3C RO data are estimated at 18 globally distributed radiosonde stations by using the three reference datasets and are compared to corresponding gridded ErrVars estimated using only the two model datasets as references. The two types of estimates show good correlations at different heights, while the gridded estimates are generally the smaller ones, which may be attributed to the neglection of error correlations among the datasets when applying the 3CH method. Due to the lack of radiosonde data in oceanic and polar regions, the global distributions of FY-3C RO observation errors are presented based on the estimated 5° × 5° gridded ErrVars. The global distribution of the FY-3C RO fractional error standard deviations (ErrSDs) demonstrates that the observation error varies greatly at different pressure levels and latitudes. Specifically, the refractivity ErrSDs at 200 hPa and 50 hPa are significantly higher around 30°N and 30°S than in other areas. The specific humidity ErrSDs generally increase as pressure levels decrease. In addition, statistics show that the fractional ErrSDs of refractivity are generally the lowest between 45° N–75° N and 45° S–75° S at all pressure levels, and land-sea differences exist in the fractional ErrSDs for all three types of RO data.","PeriodicalId":22259,"journal":{"name":"Terrestrial, Atmospheric and Oceanic Sciences","volume":"43 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136348600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-20DOI: 10.1007/s44195-023-00053-3
De-Cheng Yi, Ray Y. Chuang, Ling-Ho Chung, Ching-Weei Lin, Ruey-Juin Rau
Abstract We present 230 field observations on the location, trending, and displacement vectors of the coseismic surface cracks induced by the 2016 Meinong earthquake in the Guanmiao area, SW Taiwan. Coseismic surface cracks trends from the north to northeast. The coseismic deformed region moved toward the W-WNW. In Guanmiao town, surface cracks were mainly distributed on both limbs of the Guanmiao syncline. The preseismic deformation was also observed along the axial trace of the Guanmiao syncline. These results give clues to high structural activities in SW Taiwan. We argue that Guanmiao syncline is an active fold with both coseismic activity and interseismic creeping, which induced nonnegligible micro-geohazards because of the continual loss. We report a new case of the normal bending-moment fault, the Luosianliao fault, which locates between the Guanmiao syncline and Chungchou anticline. However, the linkage between the shallow Luosianliao fault and the deep-seated causative fault of Guanmiao aftershocks are not known yet. We demonstrate the kinematic process of coseismic surface deformation and argue that the bending-moment fault could provide an opportunity to understand the recurrence interval of folding. The mechanism of earthquake-induced folding amplification through high fluid-pressure rocks may play a critical role in assessing earthquake hazard risks in regions with similar geology to SW Taiwan.
{"title":"Surface deformation induced by the 2016 Meinong earthquake and its implications to active folds","authors":"De-Cheng Yi, Ray Y. Chuang, Ling-Ho Chung, Ching-Weei Lin, Ruey-Juin Rau","doi":"10.1007/s44195-023-00053-3","DOIUrl":"https://doi.org/10.1007/s44195-023-00053-3","url":null,"abstract":"Abstract We present 230 field observations on the location, trending, and displacement vectors of the coseismic surface cracks induced by the 2016 Meinong earthquake in the Guanmiao area, SW Taiwan. Coseismic surface cracks trends from the north to northeast. The coseismic deformed region moved toward the W-WNW. In Guanmiao town, surface cracks were mainly distributed on both limbs of the Guanmiao syncline. The preseismic deformation was also observed along the axial trace of the Guanmiao syncline. These results give clues to high structural activities in SW Taiwan. We argue that Guanmiao syncline is an active fold with both coseismic activity and interseismic creeping, which induced nonnegligible micro-geohazards because of the continual loss. We report a new case of the normal bending-moment fault, the Luosianliao fault, which locates between the Guanmiao syncline and Chungchou anticline. However, the linkage between the shallow Luosianliao fault and the deep-seated causative fault of Guanmiao aftershocks are not known yet. We demonstrate the kinematic process of coseismic surface deformation and argue that the bending-moment fault could provide an opportunity to understand the recurrence interval of folding. The mechanism of earthquake-induced folding amplification through high fluid-pressure rocks may play a critical role in assessing earthquake hazard risks in regions with similar geology to SW Taiwan.","PeriodicalId":22259,"journal":{"name":"Terrestrial, Atmospheric and Oceanic Sciences","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135616742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Past studies have focused on the importance of hydrological variables in analyzing landslide initiation condition. Even though precipitation is the main driver of shallow landslides and debris flows, use of only rainfall-based parameters has shown some limitations. Soil moisture has been used widely to improve threshold detection capabilities. Since soil moisture directly reflects the wetness status of the ground, it can be used to identify pore pressure fluctuations more effectively. This study used rainfall and soil moisture simultaneously to capture landslide initiation conditions in detail. Results showed that continued rainfall on the day of landslide leaded to a sudden increase in soil moisture, and that soil moisture increments (∆SM) were positive in 155 out of 170 landslide cases (91%). Two simple thresholds (daily precipitation over 40 mm, ∆SM over 0) and daily precipitation (P), Antecedent Precipitation Index (API), ∆SM-based three-dimensional threshold planes having 5%, 20% probability levels were applied and compared. With respect to false alarms (FA), P-based threshold was most effective among the single thresholds (FA ranging from 24 to 28 from September 2016 to December 2019 at five validation locations). Combining P- and ∆SM-based thresholds, FA reduced without compromising the detection accuracy (2 to 3 reduction in FA). Additionally combining three-dimensional threshold with 20% probability level, FA reduced significantly (ranging from 12 to 16), at the cost of two detection failures. These findings demonstrate the need for combining precipitation and soil moisture to determine landslide thresholds.
{"title":"Three-dimensional hydrological thresholds to predict shallow landslides","authors":"Seulchan Lee, Seungcheol Oh, Ram. L. Ray, Yangwon Lee, Minha Choi","doi":"10.1007/s44195-023-00052-4","DOIUrl":"https://doi.org/10.1007/s44195-023-00052-4","url":null,"abstract":"Abstract Past studies have focused on the importance of hydrological variables in analyzing landslide initiation condition. Even though precipitation is the main driver of shallow landslides and debris flows, use of only rainfall-based parameters has shown some limitations. Soil moisture has been used widely to improve threshold detection capabilities. Since soil moisture directly reflects the wetness status of the ground, it can be used to identify pore pressure fluctuations more effectively. This study used rainfall and soil moisture simultaneously to capture landslide initiation conditions in detail. Results showed that continued rainfall on the day of landslide leaded to a sudden increase in soil moisture, and that soil moisture increments (∆SM) were positive in 155 out of 170 landslide cases (91%). Two simple thresholds (daily precipitation over 40 mm, ∆SM over 0) and daily precipitation (P), Antecedent Precipitation Index (API), ∆SM-based three-dimensional threshold planes having 5%, 20% probability levels were applied and compared. With respect to false alarms (FA), P-based threshold was most effective among the single thresholds (FA ranging from 24 to 28 from September 2016 to December 2019 at five validation locations). Combining P- and ∆SM-based thresholds, FA reduced without compromising the detection accuracy (2 to 3 reduction in FA). Additionally combining three-dimensional threshold with 20% probability level, FA reduced significantly (ranging from 12 to 16), at the cost of two detection failures. These findings demonstrate the need for combining precipitation and soil moisture to determine landslide thresholds.","PeriodicalId":22259,"journal":{"name":"Terrestrial, Atmospheric and Oceanic Sciences","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135883930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-11DOI: 10.1007/s44195-023-00051-5
Min-Hua Shen, Jia-Yuh Yu
Abstract In this study, we investigate the potential changes of El Niño characteristics, including intensity, frequency and CP/EP El Niño ratio, under progressive global warming based on the 140-year CMIP6 model simulation outputs with the 1pctCO2 experiment. Major air-sea feedback mechanisms attributing to the changes are also examined. The CMIP6 ensemble means project a slight enhancement of El Niño intensity by about 2% and a modest increase of El Niño frequency by about 4% from the first to the second 70-year periods. It is found that these small changes result from the opposite response to global warming between CP and EP El Niño, i.e., the intensity of EP El Niño is projected to weaken by nearly 4.6% while the intensity of CP El Niño is projected to increase by about 4.5%. Since CP El Niño occurs more frequently than EP El Niño in CMIP6 simulations, this leads to a slight enhancement of the total El Niño intensity if these two types of El Niño were not separated. A similar situation occurs in projecting the future change of El Niño frequency, i.e., the frequency of EP El Niño is projected to decrease by about 1.4% while the frequency of CP El Niño is projected to increase by about 2%, thereby leading to a modest increase of the total El Niño frequency. By comparing the variance explained by key air-sea feedback mechanism between the two 70-year periods, we also note that the increased CP/EP ratio can be explained by the enhanced role played by the SF (seasonal footprinting) mechanism in a warmer atmosphere. Our study also points out that, as long as a climate model can correctly produce the intensity (variance) of major air-sea feedback mechanisms, the relationship between changes in El Niño characteristics and changes in feedback mechanisms can be physically robust.
基于CMIP6模式140年模拟结果和1pctCO2实验，研究了全球变暖条件下El Niño的强度、频率和CP/EP比值的潜在变化。还研究了导致这些变化的主要海气反馈机制。CMIP6总体意味着预估El Niño强度在第一个到第二个70年周期中略有增强约2%，El Niño频率在第一个到第二个70年周期中略有增加约4%。研究发现，这些微小的变化是由CP和EP El Niño对全球变暖的相反响应引起的，EP El Niño的强度预计减弱了近4.6%，而CP El Niño的强度预计增加了约4.5%。由于在CMIP6模拟中，CP El Niño比EP El Niño发生的频率更高，如果不将这两种类型的El Niño分开，则会导致El Niño的总强度略有增强。在预测El Niño未来频率变化时也出现了类似的情况，即EP El Niño的频率预计将下降约1.4%，而CP El Niño的频率预计将增加约2%，从而导致El Niño总频率适度增加。通过比较两个70年周期间主要海气反馈机制解释的差异，我们还注意到CP/EP比值的增加可以解释为大气变暖中SF(季节性足迹)机制作用的增强。我们的研究还指出，只要气候模式能够正确地产生主要海气反馈机制的强度(方差)，El Niño特征变化与反馈机制变化之间的关系在物理上是稳健的。
{"title":"Changes in El Niño characteristics and air–sea feedback mechanisms under progressive global warming","authors":"Min-Hua Shen, Jia-Yuh Yu","doi":"10.1007/s44195-023-00051-5","DOIUrl":"https://doi.org/10.1007/s44195-023-00051-5","url":null,"abstract":"Abstract In this study, we investigate the potential changes of El Niño characteristics, including intensity, frequency and CP/EP El Niño ratio, under progressive global warming based on the 140-year CMIP6 model simulation outputs with the 1pctCO2 experiment. Major air-sea feedback mechanisms attributing to the changes are also examined. The CMIP6 ensemble means project a slight enhancement of El Niño intensity by about 2% and a modest increase of El Niño frequency by about 4% from the first to the second 70-year periods. It is found that these small changes result from the opposite response to global warming between CP and EP El Niño, i.e., the intensity of EP El Niño is projected to weaken by nearly 4.6% while the intensity of CP El Niño is projected to increase by about 4.5%. Since CP El Niño occurs more frequently than EP El Niño in CMIP6 simulations, this leads to a slight enhancement of the total El Niño intensity if these two types of El Niño were not separated. A similar situation occurs in projecting the future change of El Niño frequency, i.e., the frequency of EP El Niño is projected to decrease by about 1.4% while the frequency of CP El Niño is projected to increase by about 2%, thereby leading to a modest increase of the total El Niño frequency. By comparing the variance explained by key air-sea feedback mechanism between the two 70-year periods, we also note that the increased CP/EP ratio can be explained by the enhanced role played by the SF (seasonal footprinting) mechanism in a warmer atmosphere. Our study also points out that, as long as a climate model can correctly produce the intensity (variance) of major air-sea feedback mechanisms, the relationship between changes in El Niño characteristics and changes in feedback mechanisms can be physically robust.","PeriodicalId":22259,"journal":{"name":"Terrestrial, Atmospheric and Oceanic Sciences","volume":"239 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136098357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号