Previous studies demonstrate that the Madden-Julian Oscillation (MJO) modulates tropical cyclone (TC) activity over various locations worldwide. Since TCs are associated with anomalous large-scale circulations, they can influence the development of the MJO. However, the impact of TC on the MJO has not been thoroughly examined. This study investigates the influence of TC-associated processes on the MJO development based on the analysis of a case observed during the Dynamics of the Madden-Julian Oscillation field campaign. During the suppressed phase before the December 2011 MJO initiation, two TCs were active in the southern Tropical Indian Ocean (TIO). A dry air band within 10°S-Eq is sustained by TC-induced horizontal advection and descent, inhibiting large-scale convection in the southern equatorial IO. Consequently, convection is triggered and develops only in the northern TIO around Eq-10°N. The MJO initiates as convection develops south of the equator after the TCs dissipate.
{"title":"Influence of Indian Ocean Tropical Cyclones on the Development of the Madden-Julian Oscillation in December 2011","authors":"Suyang Pei, Toshiaki Shinoda","doi":"10.1029/2024gl111502","DOIUrl":"https://doi.org/10.1029/2024gl111502","url":null,"abstract":"Previous studies demonstrate that the Madden-Julian Oscillation (MJO) modulates tropical cyclone (TC) activity over various locations worldwide. Since TCs are associated with anomalous large-scale circulations, they can influence the development of the MJO. However, the impact of TC on the MJO has not been thoroughly examined. This study investigates the influence of TC-associated processes on the MJO development based on the analysis of a case observed during the Dynamics of the Madden-Julian Oscillation field campaign. During the suppressed phase before the December 2011 MJO initiation, two TCs were active in the southern Tropical Indian Ocean (TIO). A dry air band within 10°S-Eq is sustained by TC-induced horizontal advection and descent, inhibiting large-scale convection in the southern equatorial IO. Consequently, convection is triggered and develops only in the northern TIO around Eq-10°N. The MJO initiates as convection develops south of the equator after the TCs dissipate.","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"74 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142991609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xingxu Zhou, Chao Zhang, Ziniu Xiao, Yunying Li, Gaopeng Lu
Inverse energy cascade (IEC), where energy moves from small to large eddies, has been debated, with limited observational evidence. This study used 19 months of Doppler Lidar data from Qingdao, China, to examine IEC associated with gusts. We found IECs occurred 15% of the time at 50 m height. When near-surface wind speeds exceeded 11 m·s−1, IEC frequency and intensity increased, indicating that strong winds are a critical driver of IEC. This study suggests that the reduction in the drag coefficient under high wind conditions may generate IEC and gusts, consequently influencing energy transfer throughout the boundary layer and lower troposphere. Analysis using the four-quadrant model revealed IECs are linked to changes in momentum from ejections and inward interactions, even in weak background fields. The study supports that IECs are more prevalent and highlights their role in the lower atmosphere, contributing to an improved understanding of land-atmosphere coupling.
{"title":"Inverse Energy Cascades in the Boundary Layer During Strong Winds Based on Doppler Lidar","authors":"Xingxu Zhou, Chao Zhang, Ziniu Xiao, Yunying Li, Gaopeng Lu","doi":"10.1029/2024gl113273","DOIUrl":"https://doi.org/10.1029/2024gl113273","url":null,"abstract":"Inverse energy cascade (IEC), where energy moves from small to large eddies, has been debated, with limited observational evidence. This study used 19 months of Doppler Lidar data from Qingdao, China, to examine IEC associated with gusts. We found IECs occurred 15% of the time at 50 m height. When near-surface wind speeds exceeded 11 m·s<sup>−1</sup>, IEC frequency and intensity increased, indicating that strong winds are a critical driver of IEC. This study suggests that the reduction in the drag coefficient under high wind conditions may generate IEC and gusts, consequently influencing energy transfer throughout the boundary layer and lower troposphere. Analysis using the four-quadrant model revealed IECs are linked to changes in momentum from ejections and inward interactions, even in weak background fields. The study supports that IECs are more prevalent and highlights their role in the lower atmosphere, contributing to an improved understanding of land-atmosphere coupling.","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"7 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142990525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Slope orientation creates microclimate by modulating water and heat flux between the land surface and the atmosphere, thereby regulating vegetation growth and its response to background climate change. However, the potential asymmetry in vegetation greenness between west- and east-facing slopes remains underexplored. Analyzing the normalized difference vegetation index derived from Landsat reflectances in the Tibetan Plateau (TP) grassland, we identified that west-facing slopes were greener than east-facing slopes in the western TP, while the opposite appeared in the eastern TP. We also detected a stronger greening trend on west- than east- facing slopes over the entire TP grassland from 1991 to 2020. These disparities result from distinct microclimates on the two contrasting slopes: west-facing slopes tend to be wetter and colder than east-facing slopes under similar background climate. Our findings underscore the crucial role of slope orientation in shaping vegetation greenness and its response to climate change.
{"title":"Microclimate Driven Grassland Greenness Asymmetry Between West- and East- Facing Slopes on the Tibetan Plateau","authors":"Jiangliu Xie, Xinyu Yan, Rui Chen, Yajie Yang, Yungang Cao, Yi Jian, Gaofei Yin","doi":"10.1029/2024gl113327","DOIUrl":"https://doi.org/10.1029/2024gl113327","url":null,"abstract":"Slope orientation creates microclimate by modulating water and heat flux between the land surface and the atmosphere, thereby regulating vegetation growth and its response to background climate change. However, the potential asymmetry in vegetation greenness between west- and east-facing slopes remains underexplored. Analyzing the normalized difference vegetation index derived from Landsat reflectances in the Tibetan Plateau (TP) grassland, we identified that west-facing slopes were greener than east-facing slopes in the western TP, while the opposite appeared in the eastern TP. We also detected a stronger greening trend on west- than east- facing slopes over the entire TP grassland from 1991 to 2020. These disparities result from distinct microclimates on the two contrasting slopes: west-facing slopes tend to be wetter and colder than east-facing slopes under similar background climate. Our findings underscore the crucial role of slope orientation in shaping vegetation greenness and its response to climate change.","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"30 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142990605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tropical cyclone (TC) genesis requires favorable environmental conditions and an initial disturbance, which, in the North Atlantic, is often an African easterly wave (AEW). Although studies have examined how AEWs and the environment affect TC genesis, their relative importance is less understood. Here, we examine whether AEW strength or sea surface temperatures (SSTs) are the primary drivers of TC genesis. Regional model simulations were performed to address how increased AEW strength and SSTs affect the frequency of AEWs that develop into TCs in a year with below-average TCs with AEW origins and SSTs. We found that environmental favorability plays a larger role than AEW strength in driving the frequency of TCs with AEW origins. Strengthening the AEWs did not affect the frequency of AEWs that develop into TCs due to low environmental favorability. Warmer SSTs led to increased environmental favorability and a statistically significant increase in TCs with AEW origins.
{"title":"Drivers of Atlantic Tropical Cyclogenesis: African Easterly Waves and the Environment","authors":"Emily Bercos-Hickey, Christina M. Patricola","doi":"10.1029/2024gl112002","DOIUrl":"https://doi.org/10.1029/2024gl112002","url":null,"abstract":"Tropical cyclone (TC) genesis requires favorable environmental conditions and an initial disturbance, which, in the North Atlantic, is often an African easterly wave (AEW). Although studies have examined how AEWs and the environment affect TC genesis, their relative importance is less understood. Here, we examine whether AEW strength or sea surface temperatures (SSTs) are the primary drivers of TC genesis. Regional model simulations were performed to address how increased AEW strength and SSTs affect the frequency of AEWs that develop into TCs in a year with below-average TCs with AEW origins and SSTs. We found that environmental favorability plays a larger role than AEW strength in driving the frequency of TCs with AEW origins. Strengthening the AEWs did not affect the frequency of AEWs that develop into TCs due to low environmental favorability. Warmer SSTs led to increased environmental favorability and a statistically significant increase in TCs with AEW origins.","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"205 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142990606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sean R. LaHusen, Alex R. Grant, Jonathan P. Perkins, Devin McPhillips
Strong earthquakes along subduction zones are often devastating events, but sparse records along some tectonic margins limit our understanding of seismic hazards. Constraining shaking intensities is critical, especially in subduction zones with infrequent but large-magnitude earthquakes like the Cascadia Subduction Zone (CSZ), where the lack of recorded ground motions has led to uncertainty in the severity and potential impacts of future earthquakes. Here we fill this observational gap with a novel inventory of quantitative estimates of past shaking intensities from geotechnical modeling of coastal landforms. One hundred fifty-four deep-seated landslides and 65 fragile geologic features constrain minimum and maximum peak ground accelerations, respectively. These estimates are broadly consistent with model predictions of M9 ruptures, suggesting strong shaking of 0.4–0.8 g during past CSZ earthquakes. Local discrepancies between our geologic shaking constraints and earthquake simulations may inform past rupture behavior, leading to better predictions of shaking intensity for future earthquakes.
{"title":"Strong Shaking From Past Cascadia Subduction Zone Earthquakes Encoded in Coastal Landforms","authors":"Sean R. LaHusen, Alex R. Grant, Jonathan P. Perkins, Devin McPhillips","doi":"10.1029/2024gl112417","DOIUrl":"https://doi.org/10.1029/2024gl112417","url":null,"abstract":"Strong earthquakes along subduction zones are often devastating events, but sparse records along some tectonic margins limit our understanding of seismic hazards. Constraining shaking intensities is critical, especially in subduction zones with infrequent but large-magnitude earthquakes like the Cascadia Subduction Zone (CSZ), where the lack of recorded ground motions has led to uncertainty in the severity and potential impacts of future earthquakes. Here we fill this observational gap with a novel inventory of quantitative estimates of past shaking intensities from geotechnical modeling of coastal landforms. One hundred fifty-four deep-seated landslides and 65 fragile geologic features constrain minimum and maximum peak ground accelerations, respectively. These estimates are broadly consistent with model predictions of M9 ruptures, suggesting strong shaking of 0.4–0.8 g during past CSZ earthquakes. Local discrepancies between our geologic shaking constraints and earthquake simulations may inform past rupture behavior, leading to better predictions of shaking intensity for future earthquakes.","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"24 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142989056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shengyi Qian, Haibo Hu, Kevin I. Hodges, Xiu-Qun Yang
The Arctic Oscillation (AO) is the most significant mode of sea level pressure (SLP) anomalies in the Northern Hemisphere, exhibiting significant multiple-timescale variability from synoptic to decadal. Using NCEP Climate Forecast System Reanalysis data from 1979 to 2022 during the cold season (November–April), this study identifies the relationship between the number of extra-tropical cyclones entering and exiting the Arctic and the AO synoptic variability. The Joint Net Cyclone Flux (JNCF) is significantly correlated with the spatio-temporal evolution of the synoptic AO and the composites of SLP associated with the JNCF produce AO-like patterns. Subsequent piecewise potential vorticity inversion reveals the impacts of extratropical cyclones on the synoptic-scale AO-like geopotential height anomalies at different altitudes. The effects of extratropical cyclones are more important than Arctic stratospheric PV intrusions. Furthermore, the upper-level dynamic processes among all extratropical cyclone effects dominate the evolution of synoptic-scale AO-like geopotential height anomalies.
北极涛动（AO）是北半球海平面气压（SLP）异常的最重要模态，表现出从天气到年代际的显著多时间尺度变化。利用1979 ~ 2022年寒季（11 ~ 4月）NCEP气候预报系统再分析资料，研究了进入和离开北极的热带外气旋数量与AO天气变率的关系。联合净气旋通量（Joint Net Cyclone Flux， JNCF）与天气性AO的时空演变有显著的相关性，与JNCF相关的SLP复合会产生类似AO的模式。随后的逐段位涡度反演揭示了温带气旋对不同高度的天气尺度类ao位势高度异常的影响。温带气旋的影响比北极平流层PV入侵更重要。此外，所有温带气旋效应中的高层动力过程主导了天气尺度类ao位势高度异常的演变。
{"title":"Do Extratropical Cyclones Impact Synoptic-Scale Variability of the Arctic Oscillation During Cold Season?","authors":"Shengyi Qian, Haibo Hu, Kevin I. Hodges, Xiu-Qun Yang","doi":"10.1029/2024gl112747","DOIUrl":"https://doi.org/10.1029/2024gl112747","url":null,"abstract":"The Arctic Oscillation (AO) is the most significant mode of sea level pressure (SLP) anomalies in the Northern Hemisphere, exhibiting significant multiple-timescale variability from synoptic to decadal. Using NCEP Climate Forecast System Reanalysis data from 1979 to 2022 during the cold season (November–April), this study identifies the relationship between the number of extra-tropical cyclones entering and exiting the Arctic and the AO synoptic variability. The Joint Net Cyclone Flux (JNCF) is significantly correlated with the spatio-temporal evolution of the synoptic AO and the composites of SLP associated with the JNCF produce AO-like patterns. Subsequent piecewise potential vorticity inversion reveals the impacts of extratropical cyclones on the synoptic-scale AO-like geopotential height anomalies at different altitudes. The effects of extratropical cyclones are more important than Arctic stratospheric PV intrusions. Furthermore, the upper-level dynamic processes among all extratropical cyclone effects dominate the evolution of synoptic-scale AO-like geopotential height anomalies.","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"8 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142989057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Large scale geological storage of CO2 is being deployed worldwide to reduce greenhouse gas emissions to the atmosphere. Previous modeling studies have investigated the potential for CO2 migration along faults. We observe such migration at a commercial-scale, demonstration CO2 storage project, including subsequent emergence of the CO2 into overlying permeable layers. Previous attempts at interpreting the time-lapse seismic data using amplitude attributes were hindered by noise from the limited survey repeatability combined with a weak signal due to the stiffness of the rock. Here we apply an alternative interpretation of the seismic data using time shift attributes, resulting in clear plume anomalies. In addition to migrating up the fault, we observe the plume diverted by the start of injection at a neighboring project. This work provides field observations of theorized plume behaviors and demonstrates an alternative approach to overcome challenges in interpreting seismic monitoring data for geological CO2 storage.
{"title":"Carbon Dioxide Migration Along Faults at the Illinois Basin—Decatur Project Revealed Using Time Shift Analysis of Seismic Monitoring Data","authors":"I. Bukar, R. Bell, A. H. Muggeridge, S. Krevor","doi":"10.1029/2024gl110049","DOIUrl":"https://doi.org/10.1029/2024gl110049","url":null,"abstract":"Large scale geological storage of CO<sub>2</sub> is being deployed worldwide to reduce greenhouse gas emissions to the atmosphere. Previous modeling studies have investigated the potential for CO<sub>2</sub> migration along faults. We observe such migration at a commercial-scale, demonstration CO<sub>2</sub> storage project, including subsequent emergence of the CO<sub>2</sub> into overlying permeable layers. Previous attempts at interpreting the time-lapse seismic data using amplitude attributes were hindered by noise from the limited survey repeatability combined with a weak signal due to the stiffness of the rock. Here we apply an alternative interpretation of the seismic data using time shift attributes, resulting in clear plume anomalies. In addition to migrating up the fault, we observe the plume diverted by the start of injection at a neighboring project. This work provides field observations of theorized plume behaviors and demonstrates an alternative approach to overcome challenges in interpreting seismic monitoring data for geological CO<sub>2</sub> storage.","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"30 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142989055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Paleocene–Eocene Thermal Maximum (PETM; ∼56 Ma) was a period of extreme global warming associated with a massive influx of isotopically light carbon into the ocean–atmosphere system. The burning of Paleocene peatland (wildfire hypothesis) has been proposed as a potential light carbon source. In addition, numerical models have predicted that wildfire activity would intensify in response to CO2-induced global warming. In this study, we tested the wildfire hypothesis and model prediction by tracing the wildfire history across the PETM in East Asia using polycyclic aromatic hydrocarbons (PAHs). The PAH record exhibited notable spatiotemporal heterogeneity, indicating that wildfire activity varied widely across different regions and time periods during the PETM and highlighting the complex interplay between climate, vegetation, and fire dynamics. Global wildfire records do not support the global burning of Paleocene peatland; therefore, a wildfire-related light carbon source requires close scrutiny.
{"title":"Two Sites in East Asia Add to Spatiotemporal Heterogeneity of Wildfire Activity Across the Paleocene–Eocene Thermal Maximum","authors":"Zuoling Chen, Chenyan Li, Shiling Yang, Peizong Lü, Zihua Tang, Jimin Sun, Xijun Ni, Linhao Fang, Zhongli Ding","doi":"10.1029/2024gl113829","DOIUrl":"https://doi.org/10.1029/2024gl113829","url":null,"abstract":"The Paleocene–Eocene Thermal Maximum (PETM; ∼56 Ma) was a period of extreme global warming associated with a massive influx of isotopically light carbon into the ocean–atmosphere system. The burning of Paleocene peatland (wildfire hypothesis) has been proposed as a potential light carbon source. In addition, numerical models have predicted that wildfire activity would intensify in response to CO<sub>2</sub>-induced global warming. In this study, we tested the wildfire hypothesis and model prediction by tracing the wildfire history across the PETM in East Asia using polycyclic aromatic hydrocarbons (PAHs). The PAH record exhibited notable spatiotemporal heterogeneity, indicating that wildfire activity varied widely across different regions and time periods during the PETM and highlighting the complex interplay between climate, vegetation, and fire dynamics. Global wildfire records do not support the global burning of Paleocene peatland; therefore, a wildfire-related light carbon source requires close scrutiny.","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"7 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yiyao Li, Daorui Han, Cheryl A. Rogers, Sarah A. Finkelstein, Oleksandra Hararuk, James M. Waddington, Carlos Barreto, James W. McLaughlin, James Snider, Alemu Gonsamo
The Hudson Bay Lowlands (HBL) are recognized as the second largest peatland complex in the world. Due to variability in peat thickness across a large and heterogeneous landscape, the existing carbon (C) storage estimates for the HBL may contain large uncertainty. Here, we use geospatial variables that are associated with HBL peat formation, age, accumulation, and occurrence to understand the driving factors for peat depth variability and map peat depth and C storage at 30 m spatial resolution. The estimated average peat depth of HBL is 184(±48) cm with 90% of values falling between 89 and 264 cm. Based on the spatially explicit peat depth, the HBL total C storage is estimated to be 30(±6) Pg. Distance to the coastline is the most important indicator of peat depth where the depth increases with distance further away from Hudson Bay coastline, confirming that the time since peat formation is closely related to peat depth.
{"title":"Peat Depth and Carbon Storage of the Hudson Bay Lowlands, Canada","authors":"Yiyao Li, Daorui Han, Cheryl A. Rogers, Sarah A. Finkelstein, Oleksandra Hararuk, James M. Waddington, Carlos Barreto, James W. McLaughlin, James Snider, Alemu Gonsamo","doi":"10.1029/2024gl110679","DOIUrl":"https://doi.org/10.1029/2024gl110679","url":null,"abstract":"The Hudson Bay Lowlands (HBL) are recognized as the second largest peatland complex in the world. Due to variability in peat thickness across a large and heterogeneous landscape, the existing carbon (C) storage estimates for the HBL may contain large uncertainty. Here, we use geospatial variables that are associated with HBL peat formation, age, accumulation, and occurrence to understand the driving factors for peat depth variability and map peat depth and C storage at 30 m spatial resolution. The estimated average peat depth of HBL is 184(±48) cm with 90% of values falling between 89 and 264 cm. Based on the spatially explicit peat depth, the HBL total C storage is estimated to be 30(±6) Pg. Distance to the coastline is the most important indicator of peat depth where the depth increases with distance further away from Hudson Bay coastline, confirming that the time since peat formation is closely related to peat depth.","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"96 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. O. Reznychenko, D. V. Kotov, P. G. Richards, O. V. Bogomaz, A. I. Reznychenko, L. P. Goncharenko, T. G. Zhivolup, I. F. Domnin
Observation-based simulations of the ionosphere were performed with the NRLMSISE-00 model for six locations around the globe during 1–9 February 2022, which includes the so-called Starlink Storm. Unlike other studies, we focused on the magnetically quiet days around the storm. Unexpectedly, the observed values of the F2-layer peak density were ∼50% larger than the simulated values. We show that this implies that the daytime O density in the thermosphere was systematically ∼30% larger than the NRLMSISE-00 predicts. Further investigation shows that this discrepancy is not an exclusive feature of the period around the Starlink Storm and a similar problem happens for some periods for different years. It is unclear if the reason is an actual increase of the O density or its underestimation by the model. Resolving this problem is critical for providing accurate predictions of the atmosphere to avoid the degradation of normal operation or even loss of space assets.
{"title":"The Thermosphere Was Poorly Predictable Not Only During but Also Before and After the Starlink Storm on 3–4 February 2022","authors":"M. O. Reznychenko, D. V. Kotov, P. G. Richards, O. V. Bogomaz, A. I. Reznychenko, L. P. Goncharenko, T. G. Zhivolup, I. F. Domnin","doi":"10.1029/2024gl112620","DOIUrl":"https://doi.org/10.1029/2024gl112620","url":null,"abstract":"Observation-based simulations of the ionosphere were performed with the NRLMSISE-00 model for six locations around the globe during 1–9 February 2022, which includes the so-called Starlink Storm. Unlike other studies, we focused on the magnetically quiet days around the storm. Unexpectedly, the observed values of the F2-layer peak density were ∼50% larger than the simulated values. We show that this implies that the daytime O density in the thermosphere was systematically ∼30% larger than the NRLMSISE-00 predicts. Further investigation shows that this discrepancy is not an exclusive feature of the period around the Starlink Storm and a similar problem happens for some periods for different years. It is unclear if the reason is an actual increase of the O density or its underestimation by the model. Resolving this problem is critical for providing accurate predictions of the atmosphere to avoid the degradation of normal operation or even loss of space assets.","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"55 1","pages":""},"PeriodicalIF":5.2,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：