Atmosphere-Ocean最新文献

{"title":"Droughts and Mega-Droughts","authors":"Jialin Lin, Taotao Qian, S. Schubert","doi":"10.1080/07055900.2022.2086848","DOIUrl":"https://doi.org/10.1080/07055900.2022.2086848","url":null,"abstract":"ABSTRACT Drought is the deadliest natural disaster on Earth due to its long duration, wide spatial coverage and direct connection with the food supply for human beings. Drought develops slowly and thus is called a silent killer. This paper reviews the history of research on droughts and mega-droughts. Interannual droughts are in many places driven by the El Nino-Southern Oscillation, multi-decadal mega-droughts are often driven by the Atlantic Multi-Decadal Oscillation, while centennial mega-droughts are often driven by the Global Inter-Centennial Oscillation. More generally, droughts are affected by multiple factors including global sea surface temperature anomalies, local land-atmosphere feedbacks, internal atmospheric variability and external forcings from outside the climate system. Possible future research directions are also suggested.","PeriodicalId":55434,"journal":{"name":"Atmosphere-Ocean","volume":"60 1","pages":"245 - 306"},"PeriodicalIF":1.2,"publicationDate":"2022-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45178116","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}

{"title":"Applications of the Three-cornered Hat Method to the Error Variance Estimations of FY-4A Atmospheric Temperature Profiles","authors":"Yue Zhang, Yudong Gao, Xueming Xu, Fang Zhao","doi":"10.1080/07055900.2022.2096559","DOIUrl":"https://doi.org/10.1080/07055900.2022.2096559","url":null,"abstract":"ABSTRACT This study applied the three-cornered hat method to the error variance estimations of temperature profiles retrieved from the Geosynchronous Interferometric Infrared Sounder (GIIRS), the first hyperspectral infrared sounder onboard Fengyun-4A (FY-4A) geostationary satellite. An accurate observational error is a crucial input parameter for FY-4A temperature profile assimilation. Using multiple data sets from 2020, this study examined the error variances of FY-4A temperature profiles in clear-sky and cloudy-sky respectively. Because of the effects of clouds on GIIRS, the error variances in cloudy-sky are much larger than in clear-sky. Provided that error variances less than 4K2 are significant for data assimilation, the FY-4A temperature profiles in clear-sky from 900 to 150 hPa are meaningful to be assimilated. Results reveal that the latitudinal dependency of error variances is strong at 100 hPa. Encouraged by the vertical distributions of the temperature profile differences between FY-4A and other data sets, the error variance of total potential energy is also examined in this study. Although the detailed structures of temperature profiles are removed, the vertical integration obtains a more minor percentage error. Further studies on data assimilation are worth discussing if total potential energy is more meaningful than the FY-4A temperature profiles.","PeriodicalId":55434,"journal":{"name":"Atmosphere-Ocean","volume":"61 1","pages":"12 - 24"},"PeriodicalIF":1.2,"publicationDate":"2022-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49612727","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}

{"title":"The Atlantic Multi-Decadal Oscillation","authors":"Jialin Lin, Taotao Qian","doi":"10.1080/07055900.2022.2086847","DOIUrl":"https://doi.org/10.1080/07055900.2022.2086847","url":null,"abstract":"ABSTRACT This paper reviews the history of research on the Atlantic Multi-decadal Oscillation (AMO), including its dynamics, global teleconnections, global impacts, and connection to global mean surface temperature. The AMO is a global-scale coupled ocean-atmosphere oscillation of the climate system with significant sea surface temperature (SST) anomalies in all ocean basins. It is associated with significant oscillation of the Atlantic Meridional Overturning Circulation (AMOC), which is likely driven by tidal gravitational forcing through tidal mixing and enhanced by volcano forcing and cloud-radiation feedback. The AMO strongly affects surface air temperature (Tair) and Palmer Drought Severity Index (PDSI) over all the continents. The phase lag varies among different continents. Over the tropical continents, Tair and PDSI tend to be in phase with each other. Over the extratropical continents, Tair and PDSI tend to be out of phase with each other. The AMO contributes significantly to global mean surface temperature and global warming hiatus.","PeriodicalId":55434,"journal":{"name":"Atmosphere-Ocean","volume":"60 1","pages":"307 - 337"},"PeriodicalIF":1.2,"publicationDate":"2022-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42844891","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}

{"title":"Development of Moist Singular Vectors in GRAPES-GEPS and a Preliminary Evaluation","authors":"Jing Wang, Jing Chen, Yongzhu Liu, Juanjuan Liu, Bin Wang, Xiaoli Li, Fajing Chen, Z. Huo","doi":"10.1080/07055900.2022.2092445","DOIUrl":"https://doi.org/10.1080/07055900.2022.2092445","url":null,"abstract":"ABSTRACT In this study, moist singular vector (MSV) was developed based on GRAPES-GEPS (Global/Regional Assimilation and Prediction System – Global Ensemble Prediction System), the adjoint model of large-scale condensation and cumulus deep convection in GRAPES-4DVar (Four-dimensional variational assimilation). Five consecutive days of numerical experiments were performed for a preliminary evaluation of MSV. The singular values, horizontal distribution structure, spread of MSVs perturbation and its influence on the ensemble prediction were compared for each group of tests. The results showed that in the middle and high latitudes of the northern and southern hemispheres, the addition of both linearized moist physical processes increased the spread of the mid- and low-level SVs, but the linearized large-scale condensation (LC) process plays a leading role in the structure of MSV. The analysis of ensemble forecast shows the inclusion of moist linearized physical processes led to a greater effect of MSV on the rainfall levels of 10 and 25 mm and a slight improvement in anomaly correlation coefficient (ACC) of the atmospheric circulation field, and more obvious improvement due to linearized large-scale condensation. In the future, continuous multi-year testing and tropical-specific analyses are required for operation.","PeriodicalId":55434,"journal":{"name":"Atmosphere-Ocean","volume":"61 1","pages":"57 - 67"},"PeriodicalIF":1.2,"publicationDate":"2022-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49086150","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}

{"title":"Introduction to the Special Issue on Earth’s Climate and Weather: Dominant Variability and Disastrous Extremes","authors":"Jialin Lin, Hai Lin","doi":"10.1080/07055900.2022.2087590","DOIUrl":"https://doi.org/10.1080/07055900.2022.2087590","url":null,"abstract":"We live on beautiful Planet Earth, which was born 4.6 billion years ago along with the rest of the solar system. Earth consists of an atmosphere, biosphere, hydrosphere and geosphere. Most of the time, Earth’s weather and climate are benevolent. We can hike in the forest, stand on a mountain top, lie down on the beach, and surf on the sea. With the advances of modern science and technology, we can also explore the poles and Mount Everest, dive into the Challenger Deep in the Mariana Trench, and even take measurements of Earth from space. However, once in a while, extreme weather and climate events hit the world, such as tropical cyclones, winter blizzards, summer heat waves, tornadoes, floods, and droughts. Sometimes, a mega-drought can last for decades or centuries. Throughout history, persistent mega-droughts drove the migration of early humans out of Africa (Scholz et al., 2007), the Migration Period and collapse of Western Roman Empire in Europe (Buntgen et al., 2011), the collapse of Maya civilization in the Americas (Kennett et al., 2012), and the collapses of several dynasties in China (Zhang et al., 2008). As we enter the new millennium, weatherand climate-related disasters are still frequently causing large numbers of fatalities and costly property damage (e.g. Goodkind & West, 2001; United Nation News, 2013). Three of the deadliest heat waves of the last decade caused 128,500 fatalities in France, Russia, India and Pakistan (Haider & Anis, 2015; McMichael & Lindgren, 2011; Reuters, 2015; Robine et al., 2008). Cyclone Nargis killed 138,000 people in Bangladesh in 2008 (Fritz et al., 2009). In the United States, $268 billion in damage was caused by three major hurricanes in 2017 (NOAA NCEI, 2018), which wiped out 60% of the country’s annual GDP growth in that year. The large number of fatalities and high cost of damage in recent years reflect the persistent difficulty in predicting weatherand climate-related disasters. For example, we still cannot predict the rapid intensification of hurricanes (Cangialosi, 2020), the occurrence of deadly tornadoes (Brooks et al., 2019), and the occurrence of widespread droughts around the world. The Earth’s climate is a complex system with strong feedbacks among its different components, i.e. the atmosphere, ocean, land, sea ice and biogeochemistry. Earth’s climate also covers a very wide range of time and spatial scales, from billions of years to seconds and from the whole globe to 10 metres. The key phenomena are summarized in Figure 1. Generally, weather refers to the shortterm, small-scale phenomena that last for seconds up to about half a month, and occur over one community, one state or one country, while climate refers to long-term, large-scale phenomena that last for one season up to 4.5 billion years, and occur over one continent, one ocean basin or the whole globe. The intraseasonal variability lies in between and connects weather and climate. In order to predict weatherand climate-related disa","PeriodicalId":55434,"journal":{"name":"Atmosphere-Ocean","volume":"60 1","pages":"141 - 148"},"PeriodicalIF":1.2,"publicationDate":"2022-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45962368","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}

{"title":"Freezing Rain Events that Impacted the Province of New Brunswick, Canada, and Their Evolution in a Warmer Climate","authors":"J. Chartrand, J. Thériault, Sébastien Marinier","doi":"10.1080/07055900.2022.2092444","DOIUrl":"https://doi.org/10.1080/07055900.2022.2092444","url":null,"abstract":"ABSTRACT Winter storms in eastern Canada can bring heavy precipitation, including large amounts of freezing rain. The resulting ice accumulation on structures such as trees and power lines can lead to widespread power outages and damage to infrastructure. The objective of this study is to provide a better understanding of the processes that led to extreme freezing rain events over New Brunswick (NB), Canada, during past events and how they may change in the future. To accomplish this, freezing rain events that affected the power network over NB were identified and analysed using high-resolution convection-permitting simulations. These simulations were produced from 2000 to 2013 climate data and using the pseudo global warming (WRF-PGW) approach, assuming warmer climate conditions. Our results show that through the process of cold air damming, the Appalachians enhance the development of strong temperature inversions, leading to an increase in the amount of freezing rain in central and southern NB. The occurrence of freezing rain events generally decreases by 40% in southern and eastern NB, while the occurrence of long-duration events (>6 h) increases slightly in northwestern NB in the WRF-PGW simulation. Overall, key local orographic effects that influence atmospheric conditions favorable for freezing precipitation were identified. This knowledge will enable us to better anticipate the impact of climate change on similar storms.","PeriodicalId":55434,"journal":{"name":"Atmosphere-Ocean","volume":"61 1","pages":"40 - 56"},"PeriodicalIF":1.2,"publicationDate":"2022-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46693643","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}

{"title":"Atmospheric Convection","authors":"Jialin Lin, Taotao Qian, P. Bechtold, G. Grell, Guang J. Zhang, Ping Zhu, S. Freitas, H. Barnes, Jongil Han","doi":"10.1080/07055900.2022.2082915","DOIUrl":"https://doi.org/10.1080/07055900.2022.2082915","url":null,"abstract":"ABSTRACT Convective parameterization is the long-lasting bottleneck of global climate modelling and one of the most difficult problems in atmospheric sciences. Uncertainty in convective parameterization is the leading cause of the widespread climate sensitivity in IPCC global warming projections. This paper reviews the observations and parameterizations of atmospheric convection with emphasis on the cloud structure, bulk effects, and closure assumption. The representative state-of-the-art convection schemes are presented, including the ECMWF convection scheme, the Grell scheme used in NCEP model and WRF model, the Zhang-MacFarlane scheme used in NCAR and DOE models, and parameterizations of shallow moist convection. The observed convection has self-suppression mechanisms caused by entrainment in convective updrafts, surface cold pool generated by unsaturated convective downdrafts, and warm and dry lower troposphere created by mesoscale downdrafts. The post-convection environment is often characterized by “diamond sounding” suggesting an over-stabilization rather than barely returning to neutral state. Then the pre-convection environment is characterized by slow moistening of lower troposphere triggered by surface moisture convergence and other mechanisms. The over-stabilization and slow moistening make the convection events episodic and decouple the middle/upper troposphere from the boundary layer, making the state-type quasi-equilibrium hypothesis invalid. Right now, unsaturated convective downdrafts and especially mesoscale downdrafts are missing in most convection schemes, while some schemes are using undiluted convective updrafts, all of which favour easily turned-on convection linked to double-ITCZ (inter-tropical convergence zone), overly weak MJO (Madden-Julian Oscillation) and precocious diurnal precipitation maximum. We propose a new strategy for convection scheme development using reanalysis-driven model experiments such as the assimilation runs in weather prediction centres and the decadal prediction runs in climate modelling centres, aided by satellite simulators evaluating key characteristics such as the lifecycle of convective cloud-top distribution and stratiform precipitation fraction.","PeriodicalId":55434,"journal":{"name":"Atmosphere-Ocean","volume":"60 1","pages":"422 - 476"},"PeriodicalIF":1.2,"publicationDate":"2022-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47973394","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}

{"title":"Evaluation of Data-driven Hybrid Machine Learning Algorithms for Modelling Daily Reference Evapotranspiration","authors":"N. L. Kushwaha, Jitendra Rajput, D. Sena, A. Elbeltagi, Dhananjai Singh, I. Mani","doi":"10.1080/07055900.2022.2087589","DOIUrl":"https://doi.org/10.1080/07055900.2022.2087589","url":null,"abstract":"ABSTRACT Reference evapotranspiration (ET0) is one of the crucial variables used for irrigation scheduling, agricultural production, and water balance studies. This study compares six different models with sequential inclusion of six meteorological input variables such as minimum temperature (Tmin), maximum temperature (Tmax), mean relative humidity (RH), wind speed (SW), sunshine hours (HSS), and solar radiation (RS), which are necessarily used in physical or empirical-based models to estimate ET0. Each model utilized three variants of machine learning algorithms, i.e. Additive Regression (AdR), Random Subspace (RSS), M5 Pruning tree (M5P) independently and four novel permutated hybrid combinations of these algorithms. To evaluate the efficacy of these hybridizations and the stability of machine learning models, a comprehensive evaluation of independent and hybrid models was performed. With more input variables, the model performances were found to be superior in terms of prediction accuracies. The model AdR6 that included all the 6 selected meteorological variables outperformed other models during the testing period, exhibiting statistical performance of MAPE (1.30), RMSE (0.07), RAE (2.41), RRSE (3.10), and R 2 (0.998). However, the AdR algorithm, alone, was found to capture about 86% of variance in the observed data conforming to the 95% confidence band across all models irrespective of the number of input variables used to predict ET0. The RSS algorithm, in comparison to other algorithms, failed to capture the observed trends even with all the input variables. The hybrid combinations of algorithms with AdR as a constituent were better performers in terms of their prediction accuracies but remained inferior to AdR as an individual performer. All the algorithms are better predictors of the higher values of ET0 that included values beyond the 75% quartile.","PeriodicalId":55434,"journal":{"name":"Atmosphere-Ocean","volume":"60 1","pages":"519 - 540"},"PeriodicalIF":1.2,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46400339","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}

{"title":"Atmospheric Observations of Weather and Climate","authors":"H. Bluestein, F. Carr, S. Goodman","doi":"10.1080/07055900.2022.2082369","DOIUrl":"https://doi.org/10.1080/07055900.2022.2082369","url":null,"abstract":"ABSTRACT Current observation systems that provide data for the analysis and prediction of climate and day-to-day weather are described, along with plans for future systems. The basic principles of satellite, radar, lidar, and sodar measurements are summarized. Temperature and moisture measurements on planetary and synoptic scales, ranging from satellites, the radiosonde network, aircraft, and other sounding systems are described. Wind measurements from satellites, rawinsondes, air composition from satellites, the energy budget, and surface measurements are also discussed. The measuring systems for mesoscale and convective-scale weather are then noted, including satellite-borne radiation instrumentation, and lightning imaging sensors. Operational, fixed-site, and mobile and airborne research radars, surface instrumentation, and ground-based and in-situ profiling systems, aircraft-borne and shipborne instrumentation are also summarized. Special observation issues such as coordination among providers, data assimilation considerations, and data curation are then considered. Special issues for the future are noted in the last section.","PeriodicalId":55434,"journal":{"name":"Atmosphere-Ocean","volume":"60 1","pages":"149 - 187"},"PeriodicalIF":1.2,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45775100","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}

{"title":"The Pleistocene Glacial Cycles and Millennial-Scale Climate Variability","authors":"P. Ditlevsen","doi":"10.1080/07055900.2022.2077172","DOIUrl":"https://doi.org/10.1080/07055900.2022.2077172","url":null,"abstract":"ABSTRACT The Pleistocene glacial cycles are the most prominent climate variations over the past three million years. They are the climatic response to variations in the incoming solar radiation, insolation, due to the deviations of the Earth's orbital configuration from the perfect Keplerian orbit is caused by the influence of the other planets in the solar system. This climatic response to astronomical forcing is highly non-linear, which is most pronounced expressed in the changing duration of the glacial cycles through the Middle Pleistocene Transition around a million years ago, where the duration of glacial cycles changed from 40 kyr to approximately 100 kyr without any corresponding changes in the astronomical forcing. In the late Pleistocene glaciations, the Northern Hemisphere ice sheets have grown larger than before, causing an increased cooling through the ice-albedo feedback, which makes it harder with increased insolation to cause deglaciation. The cold climate with extended glaciations has also made the climate more unstable, where strong millennial-scale oscillations related to changes in the Atlantic Meridional Overturning Circulation are observed in the paleoclimatic records.","PeriodicalId":55434,"journal":{"name":"Atmosphere-Ocean","volume":"60 1","pages":"233 - 244"},"PeriodicalIF":1.2,"publicationDate":"2022-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43722578","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}