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Shunlin Liang, Jie Cheng, Kun Jia, Bo Jiang, Qiang Liu, Zhiqiang Xiao, Yunjun Yao, Wenping Yuan, Xiaotong Zhang, Xiang Zhao, and Ji Zhou

Abstract:

The Global Land Surface Satellite (GLASS) product suite currently contains 12 products, including leaf area index, fraction of absorbed photosynthetically active radiation, fraction of green vegetation coverage, gross primary production, broadband albedo, broadband longwave emissivity, downward shortwave radiation and photosynthetically active radiation, land surface temperature, downward and upwelling thermal radiation, all-wave net radiation, and evapotranspiration. These products are generated from the Advanced Very High Resolution Radiometer and Moderate Resolution Imaging Spectroradiometer satellite data. Their unique features include long-term temporal coverage (many from 1981 to the present), high spatial resolutions of the surface radiation products (1 km and 0.05°), spatial continuities without missing pixels, and high quality and accuracy based on extensive validation using in situ measurements and intercomparisons with other existing satellite products. Moreover, the GLASS products are based on robust algorithms that have been published in peer-reviewed literature. Herein, we provide an overview of the algorithm development, product characteristics, and some preliminary applications of these products. We also describe the next steps, such as improving the existing GLASS products, generating more climate data records (CDRs), broadening product dissemination, and fostering their wider utilization. The GLASS products are freely available to the public.

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Stephan T. Kral, Joachim Reuder, Timo Vihma, Irene Suomi, Kristine F. Haualand, Gabin H. Urbancic, Brian R. Greene, Gert-Jan Steeneveld, Torge Lorenz, Björn Maronga, Marius O. Jonassen, Hada Ajosenpää, Line Båserud, Phillip B. Chilson, Albert A. M. Holtslag, Alastair D. Jenkins, Rostislav Kouznetsov, Stephanie Mayer, Elizabeth A. Pillar-Little, Alexander Rautenberg, Johannes Schwenkel, Andrew W. Seidl, and Burkhard Wrenger

Abstract

The Innovative Strategies for Observations in the Arctic Atmospheric Boundary Layer Program (ISOBAR) is a research project investigating stable atmospheric boundary layer (SBL) processes, whose representation still poses significant challenges in state-of-the-art numerical weather prediction (NWP) models. In ISOBAR ground-based flux and profile observations are combined with boundary layer remote sensing methods and the extensive usage of different unmanned aircraft systems (UAS). During February 2017 and 2018 we carried out two major field campaigns over the sea ice of the northern Baltic Sea, close to the Finnish island of Hailuoto at 65°N. In total 14 intensive observational periods (IOPs) resulted in extensive SBL datasets with unprecedented spatiotemporal resolution, which will form the basis for various numerical modeling experiments. First results from the campaigns indicate numerous very stable boundary layer (VSBL) cases, characterized by strong stratification, weak winds, and clear skies, and give detailed insight in the temporal evolution and vertical structure of the entire SBL. The SBL is subject to rapid changes in its vertical structure, responding to a variety of different processes. In particular, we study cases involving a shear instability associated with a low-level jet, a rapid strong cooling event observed a few meters above ground, and a strong wave-breaking event that triggers intensive near-surface turbulence. Furthermore, we use observations from one IOP to validate three different atmospheric models. The unique finescale observations resulting from the ISOBAR observational approach will aid future research activities, focusing on a better understanding of the SBL and its implementation in numerical models.

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Castle A. Williams and Gina M. Eosco

ABSTRACT

Although both research and practice contend that message consistency is a critical component of effective risk communication, neither provide systematic evidence demonstrating if, when, and where consistency matters. For this reason, meteorologists view message consistency as both a relevant research and operational concern. To address these concerns, members of the weather enterprise organized conference sessions, panels, webinars, and workshops to achieve message consistency, but were unable to make progress without a definition. Fortunately, research scholars in the fields of psychology and communication studies offer important theoretical insights for defining message consistency. As such, this paper takes an important first step by combining the needs of operational meteorologists with insights from social science research to offer a definition of message consistency for the weather enterprise. While it is logical to present both a definition and a recommendation on how to achieve message consistency, the systematic review revealed various research limitations and practical constraints that call into question the feasibility of achieving it. To further bridge research and practice, this paper recommends that researchers and practitioners collaboratively develop a message consistency evaluation process for the weather enterprise. A persistent community effort will shed light on when, where, and under which circumstances consistency is necessary, and more importantly, move us one step closer toward achieving a more consistent message within the weather enterprise.

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Evert I. F. de Bruijn, Fred C. Bosveld, Siebren de Haan, and Albert A.M. Holtslag

Abstract

We report about a new third-party observation, namely, wind measurements derived from hot-air balloon (HAB) tracks. We first compare the HAB winds with wind measurements from a meteorological tower and a radio acoustic wind profiler, both situated at the topographically flat observatory near Cabauw, the Netherlands. To explore the potential of this new type of wind observation in other topographies, we present an intriguing HAB flight in Austria with a spectacular mountain–valley circulation. Subsequently, we compare the HAB data with a numerical weather prediction (NWP) model during 2011–13 and the standard deviation of the wind speed is 2.3 m s−1. Finally, we show results from a data assimilation feasibility experiment that reveals that HAB wind information can have a positive impact on a hindcasted NWP trajectory.

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Tony Bannister, Elizabeth E. Ebert, Ted Williams, Philip Douglas, Alan Wain, Maree Carroll, Jeremy Silver, Ed Newbigin, Edwin R. Lampugnani, Nicole Hughes, Clare Looker, Vanora Mulvenna, Danny Csutoros, Penelope J. Jones, Janet M. Davies, Cenk Suphioglu, Paul J. Beggs, Kathryn M. Emmerson, Alfredo Huete, and Ha Nguyen

Abstract

In November 2016, an unprecedented epidemic thunderstorm asthma event in Victoria, Australia, resulted in many thousands of people developing breathing difficulties in a very short period of time, including 10 deaths, and created extreme demand across the Victorian health services. To better prepare for future events, a pilot forecasting system for epidemic thunderstorm asthma (ETSA) risk has been developed for Victoria. The system uses a categorical risk-based approach, combining operational forecasting of gusty winds in severe thunderstorms with statistical forecasts of high ambient grass pollen concentrations, which together generate the risk of epidemic thunderstorm asthma. This pilot system provides the first routine daily epidemic thunderstorm asthma risk forecasting service in the world that covers a wide area, and integrates into the health, ambulance, and emergency management sector. Epidemic thunderstorm asthma events have historically occurred infrequently, and no event of similar magnitude has impacted the Victorian health system since. However, during the first three years of the pilot, 2017–19, two high asthma presentation events and four moderate asthma presentation events were identified from public hospital emergency department records. The ETSA risk forecasts showed skill in discriminating between days with and without health impacts. However, even with hindsight of the actual weather and airborne grass pollen conditions, some high asthma presentation events occurred in districts that were assessed as low risk for ETSA, reflecting the challenge of predicting this unusual phenomenon.

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Steven Businger

Abstract

This paper makes a case for why Hawaii is the rainbow capital of the world. It begins by briefly touching on the cultural and historical significance of rainbows in Hawaii. Next it provides an overview of the science behind the rainbow phenomenon, which provides context for exploring the meteorology that helps explain the prevalence of Hawaiian rainbows. Last, the paper discusses the art and science of chasing rainbows.

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Fan Yang, Qing He, Jianping Huang, Mamtimin Ali, Xinghua Yang, Wen Huo, Chenglong Zhou, Xinchun Liu, Wenshou Wei, Caixia Cui, Minzhong Wang, Hongjun Li, Lianmei Yang, Hongsheng Zhang, Yuzhi Liu, Xinqian Zheng, Honglin Pan, Lili Jin, Han Zou, Libo Zhou, Yongqiang Liu, Jiantao Zhang, Lu Meng, Yu Wang, Xiaolin Qin, Yongjun Yao, Houyong Liu, Fumin Xue, and Wei Zheng

CAPSULE

The Desert Environment and Climate Observation Network (DECON) could promote collaborative research on desert dust-storms, boundary-layer and land-atmosphere interactions to better understand the status and role of the Taklimakan desert.

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Jiaojiao Gou, Chiyuan Miao, Luis Samaniego, Mu Xiao, Jingwen Wu, and Xiaoying Guo

Capsule summary

A long-term spatiotemporally continuous naturalized runoff record, CNRD v1.0, is reconstructed by using a comprehensive model parameter uncertainty analysis framework within a land-surface model.

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Lei Wang, Tandong Yao, Chenhao Chai, Lan Cuo, Fengge Su, Fan Zhang, Zhijun Yao, Yinsheng Zhang, Xiuping Li, Jia Qi, Zhidan Hu, Jingshi Liu, and Yuanwei Wang

Capsule

The TP-River project is constructing a monitoring network for 13 major rivers at the Third Pole to quantify the total river runoff and its response to monsoon and westerly winds.

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Andrew Hoell, Britt-Anne Parker, Michael Downey, Natalie Umphlett, Kelsey Jencso, F. Adnan Akyuz, Dannele Peck, Trevor Hadwen, Brian Fuchs, Doug Kluck, Laura Edwards, Judith Perlwitz, Jon Eischeid, Veva Deheza, Roger Pulwarty, and Kathryn Bevington

Abstract

The 2017 flash drought arrived without early warning and devastated the U.S. northern Great Plains region comprising Montana, North Dakota, and South Dakota and the adjacent Canadian Prairies. The drought led to agricultural production losses exceeding $2.6 billion in the United States, widespread wildfires, poor air quality, damaged ecosystems, and degraded mental health. These effects motivated a multiagency collaboration among academic, tribal, state, and federal partners to evaluate drought early warning systems, coordination efforts, communication, and management practices with the goal of improving resilience and response to future droughts. This essay provides an overview on the causes, predictability, and historical context of the drought, the impacts of the drought, opportunities for drought early warning, and an inventory of lessons learned. Key lessons learned include the following: 1) building partnerships during nondrought periods helps ensure that proper relationships are in place for a coordinated and effective drought response; 2) drought information providers must improve their understanding of the annual decision cycles of all relevant sectors, including, and beyond, direct impacts in agricultural sectors; and 3) ongoing monitoring of environmental conditions is vital to drought early warning, given that seasonal forecasts lack skill over the northern Great Plains.

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