Article
Meteorology & Atmospheric Sciences
Hege-Beate Fredriksen, Maria Rugenstein, Rune Graversen
Summary: A new algorithm for estimating time-evolving global forcing in climate models is proposed, taking into account the non-constancy of global feedbacks and providing stronger forcing estimates than previously assumed. Linear temperature response functions are demonstrated to be useful for predicting responses to future scenarios.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2021)
Article
Geosciences, Multidisciplinary
Cheng-Cheng Liu, Robert W. Portmann, Shang Liu, Karen H. Rosenlof, Yifeng Peng, Pengfei Yu
Summary: This study used the Community Earth System Model to investigate the wildfire events in 2017 and 2019-2020 and found that the radiative forcing of wildfire smoke is more significant than that of equivalent sulfate aerosols, highlighting its important role in the climate radiative budget.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Environmental Sciences
N. Hirota, T. Ogura, H. Shiogama, P. Caldwell, M. Watanabe, Y. Kamae, K. Suzuki
Summary: Cloud feedback remains a major source of uncertainty in equilibrium climate sensitivity, and studies have attempted to narrow uncertainties by proposing observable metrics known as emergent constraints. A new mechanism relating convection and clouds across multiple climate models has been proposed, finding that models with overly active deep convection in subtropical low cloud regions predict smaller shortwave cloud feedback. Further improvements in understanding and modeling cloud and convective systems are necessary for accurate climate predictions.
ENVIRONMENTAL RESEARCH LETTERS
(2021)
Article
Meteorology & Atmospheric Sciences
Han Huang, Yi Huang
Summary: This study quantifies the coupling effects between different longwave radiative feedbacks using a radiative transfer model, finding that the coupling effect between water vapor and cloud is most significant and can exceed 50% of the univariate cloud feedback. This significant coupling effect is due to the masking effect of the two feedbacks on each other and can be well explained by a simple analytic model.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2021)
Article
Meteorology & Atmospheric Sciences
Fuyao Wang, Michael Notaro, Yan Yu, Jiafu Mao
Summary: This study systematically investigates and compares the simulated seasonal precipitation response in the Sahel among CMIP5 ESMs and its observational counterpart. It finds that CMIP5 models can reasonably capture the seasonal evolution of Sahel precipitation and soil moisture, although with some biases. The coupling of an ESM to a DGVM is critical in generating reasonable land-atmosphere feedback and examining future ecological and climatic changes over the Sahel.
INTERNATIONAL JOURNAL OF CLIMATOLOGY
(2023)
Article
Astronomy & Astrophysics
Naomi Rowe-Gurney, Leigh N. Fletcher, Glenn S. Orton, Michael T. Roman, Amy Mainzer, Julianne Moses, Imke de Pater, Patrick G. J. Irwin
Summary: The Spitzer Infrared Spectrometer acquired mid-infrared spectra of Uranus near its equinox in 2007, revealing significant thermal and compositional variability in its stratosphere. Longitudinal analysis showed up to 15% variability in gases sensitive to certain wavelengths at stratospheric levels. Optimal estimation inversions suggested that these variations can be explained by a temperature change of less than 3 K in the stratosphere, with potential sources localized to large scale uplift or stratospheric wave phenomena.
Article
Geosciences, Multidisciplinary
Maria A. A. Rugenstein, Kyle C. Armour
Summary: The study highlights the importance of understanding different types of radiative feedbacks, which can vary significantly over time and impact the estimated climate sensitivity. By utilizing a simple regression method with differential feedback parameter, the true equilibrium climate sensitivity could potentially be estimated within a 5% error range in as little as 400 years.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Meteorology & Atmospheric Sciences
Callum J. Shakespeare, Michael L. Roderick
Summary: This study introduces a novel methodology to decompose the impacts of increasing CO2 concentrations on downwelling longwave radiation (DLR) at Earth's surface, including direct radiative forcing and subsequent feedback mechanisms. By decomposing the feedbacks, it is found that the changes in near-surface air temperature play a dominant role in the increase of all-sky DLR, while cloud cover changes have significant impacts on DLR in specific geographical regions.
JOURNAL OF CLIMATE
(2022)
Article
Geosciences, Multidisciplinary
Yi Huang, Han Huang, Aliia Shakirova
Summary: The analysis of radiative feedbacks involves separating and quantifying the radiative contributions of different feedback variables, which may exhibit nonlinear dependencies and coupling effects. Using brute-force radiation model calculations, significant nonlinear effects were identified in the CO2-driven Arctic climate change, highlighting the need for nonlinear methods in feedback quantification.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Meteorology & Atmospheric Sciences
Christopher Hedemann, Thorsten Mauritsen, Johann Jungclaus, Jochem Marotzke
Summary: This study compares two ways of defining local radiative feedbacks in a climate model and finds that the choice of definition significantly impacts the results. These findings help to reconcile previous disagreements about which regions dominate global radiative feedback change in model simulations of global warming.
JOURNAL OF CLIMATE
(2022)
Article
Geosciences, Multidisciplinary
Jonah Bloch-Johnson, Maria Rugenstein, Martin B. Stolpe, Tim Rohrschneider, Yiyu Zheng, Jonathan M. Gregory
Summary: The equilibrium climate sensitivity, or the equilibrium warming per CO2 doubling, increases with CO2 concentration for most coupled general circulation models, with feedback temperature dependence being a key factor driving the sensitivity increase. Feedback temperature dependence is positive in the majority of models, primarily due to the longwave clear-sky feedback, and it raises the risk of extreme or runaway warming.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Meteorology & Atmospheric Sciences
Kane A. Stone, Susan Solomon, David W. J. Thompson, Douglas E. Kinnison, John C. Fyfe
Summary: This study investigates the relationship between ENSO events and the southern hemisphere (SH) stratospheric pathway. The research finds that ENSO is associated with stratospheric anomalies in the SH, with the warm phase of the ENSO cycle generally leading to a colder spring Antarctic stratosphere. This relationship is robust and consistent across multiple models. Additionally, the study reveals that the magnitude of the stratospheric pathway is weaker compared to the tropospheric pathway, playing a secondary role.
JOURNAL OF CLIMATE
(2022)
Article
Geosciences, Multidisciplinary
Matthew Jenkins, Aiguo Dai
Summary: Arctic amplification, the enhanced Arctic warming, is mainly attributed to intensified winter oceanic heating associated with sea-ice loss, aided by positive surface albedo feedback in summer and positive cloud feedback in winter.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Lukas Kluft, Sally Dacie, Manfred Brath, Stefan A. Buehler, Bjorn Stevens
Summary: This study quantifies the temperature-dependence of clear-sky climate sensitivity using a one-dimensional model, highlighting potential errors in radiation schemes that can impact climate sensitivity. Line-by-line simulations show that there is no strengthening of the longwave radiative feedback within certain temperature ranges, with a slight decrease in climate sensitivity attributed to water vapor masking radiative forcing at the flanks of the CO2 absorption band.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Matthew T. Jenkins, Aiguo Dai
Summary: In this study, seasonal variations in Arctic climate feedbacks and their relationship to sea-ice loss were investigated using ERA5 reanalysis data. The results showed that spring and summer experienced significant sea-ice loss, strong surface albedo feedback, and large oceanic heat uptake. Arctic clouds had a small net cooling effect in May-June-July but a moderate warming effect during the cold season, particularly in areas with substantial sea-ice loss. Arctic water vapor feedback reached its peak in summer but was weak and unrelated to sea-ice loss. Arctic positive lapse rate feedback (LRF) was strongest in winter over regions with significant sea-ice loss and weak inversion but was uncorrelated with atmospheric stability, indicating that oceanic heating from sea-ice loss led to enhanced surface warming and positive LRF.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Environmental Sciences
Yan Xia, Fei Xie, Xiao Lu
Summary: Surface ozone in the Arctic was significantly enhanced during the 2020-2021 winter after the onset of sudden stratospheric warming (SSW). The enhanced ozone is primarily due to the strengthening of stratosphere-to-troposphere transport associated with SSW. The SSW also leads to positive anomalies in surface ozone in the northern midlatitudes, which are related to cold air outbreaks.
ENVIRONMENTAL RESEARCH LETTERS
(2023)
Article
Meteorology & Atmospheric Sciences
Haotian Zhang, Chuanfeng Zhao, Yan Xia, Yikun Yang
Summary: This study investigates the spatial distribution of ice clouds and liquid-bearing clouds over the Greenland ice sheet (GrIS) and their effects on surface radiative forcing. The results show that the spatial and temporal variations in clouds over the GrIS are closely related to the North Atlantic Oscillation (NAO). Different regions of the GrIS exhibit different responses of clouds to changes in the atmospheric circulation field during the NAO.
JOURNAL OF CLIMATE
(2023)
Article
Meteorology & Atmospheric Sciences
Fei Xie, Yan Xia, Wuhu Feng, Yingli Niu
Summary: Excessive exposure to UV radiation harms humans and ecosystems. Surface UV radiation has been increasing significantly in the tropics and Northern Hemisphere mid-latitudes from 2010-2020, due to total column ozone depletion. The decline in stratospheric ozone after 2010 may be related to increased emissions of nitrous oxide (N2O) leading to an increase in stratospheric nitrogen oxides.
ADVANCES IN ATMOSPHERIC SCIENCES
(2023)
Article
Engineering, Ocean
Ziying Yang, Jiping Liu, Chao-Yuan Yang, Yongyun Hu
Summary: This study develops single-layer and three-hidden-layer neural networks to correct the bias in sea surface temperature forecast products from the NCEP CFSv2. The results show that both neural networks can significantly reduce the bias in the Pacific and Atlantic Oceans, with the three-hidden-layer network showing better agreement with observations in certain subregions.
JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY
(2023)
Article
Meteorology & Atmospheric Sciences
Jiawenjing Lan, Jun Yang, Yongyun Hu, Xiang Li, Jiaqi Guo, Qifan Lin, Jing Han, Jian Zhang, Shuang Wang, Ji Nie
Summary: Through using the Community Earth System Model version 1.2.2 (CESM1.2.2), it was found that the upper-tropospheric equatorial winds on ancient Earth changed to westerly flows in certain periods, forming equatorial superrotation. This phenomenon generally occurred in a warmer climate, with the tropical atmospheric circulation shifting upward in altitude, relatively stronger stationary and/or transient eddies, and relatively weaker Hadley cells, due to the changes of the three factors, especially CO2 concentration and land-sea configuration.
JOURNAL OF THE ATMOSPHERIC SCIENCES
(2023)
Article
Geography, Physical
Jian Zhang, Yongyun Hu, Chenguang Zhu, Sascha Flogel, Xiaomin Fang, Jimin Sun
Summary: This study uses the CESM 1.2.2 model to simulate the effects of global cooling and the closure of the Tethyan Seaway on the climates of North Africa and South Asia. The results show that global cooling leads to a decrease in precipitation over both regions, while the closure of the Tethyan Seaway results in a decrease in precipitation over North Africa but an increase over South Asia. The opposite effects are due to increased moisture transport from North Africa to South Asia when the Tethyan Seaway is closed. Furthermore, the study suggests that the narrowing and subsequent closure of the Tethyan Seaway contribute to the formation of the Sahara desert and the strengthening of the South Asian monsoon during the Middle Miocene.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2023)
Article
Multidisciplinary Sciences
Xiujuan Bao, Yongyun Hu, Christopher R. Scotese, Xiang Li, Jiaqi Guo, Jiawenjing Lan, Qifan Lin, Shuai Yuan, Mengyu Wei, Zhibo Li, Kai Man, Zihan Yin, Jing Han, Jian Zhang, Qiang Wei, Yonggang Liu, Jun Yang, Ji Nie
Summary: Quantitative relationships between coals and evaporites with temperature and precipitation can be established from geological records and climate simulations. The study reveals that before 250 Ma, coal records indicate a median temperature of 25 degrees C and precipitation of 1300 mm yr(-1). Afterward, coal records appear with temperatures between 0 degrees C and 21 degrees C and precipitation of 900 mm yr(-1). Evaporite records were associated with a median temperature of 27 degrees C and precipitation of 800 mm yr(-1). The most remarkable finding is the constant net precipitation associated with coal and evaporite records across time.
NATIONAL SCIENCE REVIEW
(2023)
Article
Multidisciplinary Sciences
Shiyan Zhang, Yongyun Hu, Jun Yang, Xiang Li, Wanying Kang, Jian Zhang, Yonggang Liu, Ji Nie
Summary: The Hadley circulation during the Pangea era is weaker and wider than the present, and this weakening and widening is attributed to increased tropical and subtropical static stability. The poleward shifts of the winter cell's ascending branches are associated with the geographic configuration of the supercontinent Pangea.
Editorial Material
Meteorology & Atmospheric Sciences
Minghua Zhang, Yafang Cheng, Rong Fu, Filippo Giorgi, Ruby Leung, Xin-Zhong Liang, Wahid Mellouki, William Randel, Nicole Riemer, Robert Rogers, Lynn Russell, Ping Yang, Yun Qian, Yongyun Hu, Xiushu Qie
Summary: The editorial board of JGR Atmospheres expresses gratitude to the reviewers who reviewed papers in 2022.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Editorial Material
Multidisciplinary Sciences
Yongyun Hu
CHINESE SCIENCE BULLETIN-CHINESE
(2023)
Article
Geosciences, Multidisciplinary
Yan Xia, Yongyun Hu, Yi Huang, Jianchun Bian, Chuanfeng Zhao, Jintai Lin, Fei Xie, Chunjiang Zhou
Summary: Heavy summer precipitation over the southern slope of the Tibetan Plateau has significant impacts on water resources and hydrological disasters in South Asia. The trends of this precipitation have shown an increase from 1979 to 1996, followed by a decrease from 1996 to 2022, which are not well understood. This study suggests that stratospheric ozone plays a significant role in the long-term trends of summer precipitation in this region by affecting deep convection and precipitation over the southern slope of the Tibetan Plateau. It is crucial for future water resource management in South Asia to consider the potential reduction in summer precipitation due to ozone recovery.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Yongyun Hu, Xiang Li, William R. Boos, Jiaqi Guo, Jiawenjing Lan, Qifan Lin, Jing Han, Jian Zhang, Xiujuan Bao, Shuai Yuan, Qiang Wei, Yonggang Liu, Jun Yang, Ji Nie, Zhengtang Guo
Summary: This study used a large set of simulations of global climate over the past 250 million years to reveal the evolution of the monsoon system and found that global-mean temperature variations have little impact on it. The changes in the global land monsoon are primarily governed by continental area, latitudinal location, and fragmentation.
Editorial Material
Geography, Physical
Jimin Sun, Wenjiao Xiao, Brian F. Windley, Yongyun Hu
Summary: This Special Issue consists of sixteen papers that cover the interplay between tectonics and climate in Inner Asia during the Cenozoic Era. These papers provide new insights into Cenozoic tectonism, climate changes, and their possible inter-relationships, improving our understanding of the coupling between lithosphere and surface processes. The articles will be of broad interest to interdisciplinary scholars in geosciences.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2023)
Article
Geosciences, Multidisciplinary
Jian Zhang, Sascha Floegel, Yongyun Hu, Anni Zhao, Runjian Chu, Chenguang Zhu, Chengshan Wang
Summary: The East Asian coastal mountains played a significant role in amplifying the influence of orbital forcing and solar insolation on East Asian climate during the Cretaceous period.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Astronomy & Astrophysics
Yuchen Lian, Xianyu Tan, Yongyun Hu
Summary: Observations show the existence of quasi-quadrennial oscillation (QQO) in Jupiter's equatorial stratosphere, which is caused by the downward propagation of alternating jets. A 3D general circulation model simulation suggests that injecting thermal disturbances can generate waves and result in the QQO and multiple jet streams. The evolution of potential vorticity favors the formation and migration of off-equatorial jets, which strengthen the deep equatorial jets and prolong the QQO-like oscillations.
ASTROPHYSICAL JOURNAL
(2023)