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E. RoTimi Ojo and Lynn Manaigre

Abstract

Established primarily to improve weather monitoring across the agricultural regions of the province, the Manitoba Agriculture Weather Program (MAWP) began officially in 2005 with funding from the provincial government for the establishment of a network of 28 automated weather monitoring stations. The network steadily grew to 46 stations between 2007 and 2014 as a result of partnership with local commodity and research groups. In response to the Manitoba flood of 2011, more stations were installed and the network grew to 108 weather stations in 2019. The stations are solar-powered and scheduled maintenance is conducted at each station twice per year. Weather parameters monitored include air temperature, barometric pressure, precipitation, relative humidity, soil moisture, soil temperature, solar radiation, wind speed and wind direction using research-grade sensors. The observations are transmitted via cellular telemetry every 15 minutes in the spring, summer and fall but hourly in the winter to conserve energy supply due to reduced daylight and below freezing temperatures. The data can be viewed by the public within one minute of data collection. It is used to generate agronomic-related maps such as thermal unit computation of growing degree days and corn heat units as well as disease risk maps such as Fusarium Head Blight. Beyond agriculture, the data has been used for aviation investigation and for undergraduate course instruction among other applications.

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Kristen L. Rasmussen, Melissa A. Burt, Angela Rowe, Rebecca Haacker, Deanna Hence, Lorena Medina Luna, Stephen W. Nesbitt, and Julie Maertens

Abstract

This article provides an overview of the Advanced Study Institute: Field Studies of Convection in Argentina (ASI-FSCA) program, a 3-week dynamic and collaborative hands-on experience that allowed 16 highly motivated and diverse graduate students from the U.S. to participate in the 2018-19 Remote sensing of Electrification, Lightning, And Mesoscale/microscale Processes with Adaptive Ground Observations (RELAMPAGO) field campaign. This program is unique as it represents the first effort to integrate an intensive Advanced Study Institute with a field campaign in atmospheric science. ASI-FSCA activities and successful program outcomes for five key elements are described: (1) Intensive field research with field campaign instrumentation platforms; (2) Recruitment of diverse graduate students who would not otherwise have opportunities to participate in intensive field research; (3) Tailored curriculum focused on scientific understanding of cloud and mesoscale processes and professional/academic development topics; (4) Outreach to local K-12 schools and the general public; and (5) Building a collaborative international research network to promote weather and climate research. These five elements served to increase motivation and improve confidence and self-efficacy of students to participate in scientific research and field work with goals of increasing retention and a sense of belonging in STEM graduate programs and advancing the careers of students from underrepresented groups as evidenced by a formal program evaluation effort. Given the success of the ASI-FSCA program, our team strongly recommends considering this model for expanding the opportunities for a broader and more diverse student community to participate in dynamic and intensive field work in atmospheric science.

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Eun-Pa Lim, Harry H. Hendon, Amy H. Butler, David W. J. Thompson, Zachary D. Lawrence, Adam A. Scaife, Theodore G. Shepherd, Inna Polichtchouk, Hisashi Nakamura, Chiaki Kobayashi, Ruth Comer, Lawrence Coy, Andrew Dowdy, Rene D. Garreaud, Paul A. Newman, and Guomin Wang

Abstract

This study offers an overview of the low-frequency (i.e., monthly to seasonal) evolution, dynamics, predictability, and surface impacts of a rare Southern Hemisphere (SH) stratospheric warming that occurred in austral spring 2019. Between late August and mid-September 2019, the stratospheric circumpolar westerly jet weakened rapidly, and Antarctic stratospheric temperatures rose dramatically. The deceleration of the vortex at 10 hPa was as drastic as that of the first-ever-observed major sudden stratospheric warming in the SH during 2002, while the mean Antarctic warming over the course of spring 2019 broke the previous record of 2002 by ∼50% in the midstratosphere. This event was preceded by a poleward shift of the SH polar night jet in the uppermost stratosphere in early winter, which was then followed by record-strong planetary wave-1 activity propagating upward from the troposphere in August that acted to dramatically weaken the polar vortex throughout the depth of the stratosphere. The weakened vortex winds and elevated temperatures moved downward to the surface from mid-October to December, promoting a record strong swing of the southern annular mode (SAM) to its negative phase. This record-negative SAM appeared to be a primary driver of the extreme hot and dry conditions over subtropical eastern Australia that accompanied the severe wildfires that occurred in late spring 2019. State-of-the-art dynamical seasonal forecast systems skillfully predicted the significant vortex weakening of spring 2019 and subsequent development of negative SAM from as early as late July.

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Jordan G. Powers, Kelly K. Werner, David O. Gill, Yuh-Lang Lin, and Russ S. Schumacher

Abstract

The Weather Research and Forecasting (WRF) Model is a numerical weather prediction model supported by the National Center for Atmospheric Research (NCAR) to a worldwide community of users. In recognition of the growing use of cloud computing, NCAR is now supporting the model in cloud environments. Specifically, NCAR has established WRF setups with select cloud service providers and produced documentation and tutorials on running WRF in the cloud. Described here are considerations in WRF cloud use and the supported resources, which include cloud setups for the WRF system and a cloud-based tool for model code testing.

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Catherine A. Senior, John H. Marsham, Ségolène Berthou, Laura E. Burgin, Sonja S. Folwell, Elizabeth J. Kendon, Cornelia M. Klein, Richard G. Jones, Neha Mittal, David P. Rowell, Lorenzo Tomassini, Théo Vischel, Bernd Becker, Cathryn E. Birch, Julia Crook, Andrew J. Dougill, Declan L. Finney, Richard J. Graham, Neil C. G. Hart, Christopher D. Jack, Lawrence S. Jackson, Rachel James, Bettina Koelle, Herbert Misiani, Brenda Mwalukanga, Douglas J. Parker, Rachel A. Stratton, Christopher M. Taylor, Simon O. Tucker, Caroline M. Wainwright, Richard Washington, and Martin R. Willet

Abstract

Pan-Africa convection-permitting regional climate model simulations have been performed to study the impact of high resolution and the explicit representation of atmospheric moist convection on the present and future climate of Africa. These unique simulations have allowed European and African climate scientists to understand the critical role that the representation of convection plays in the ability of a contemporary climate model to capture climate and climate change, including many impact-relevant aspects such as rainfall variability and extremes. There are significant improvements in not only the small-scale characteristics of rainfall such as its intensity and diurnal cycle, but also in the large-scale circulation. Similarly, effects of explicit convection affect not only projected changes in rainfall extremes, dry spells, and high winds, but also continental-scale circulation and regional rainfall accumulations. The physics underlying such differences are in many cases expected to be relevant to all models that use parameterized convection. In some cases physical understanding of small-scale change means that we can provide regional decision-makers with new scales of information across a range of sectors. We demonstrate the potential value of these simulations both as scientific tools to increase climate process understanding and, when used with other models, for direct user applications. We describe how these ground-breaking simulations have been achieved under the U.K. Government’s Future Climate for Africa Programme. We anticipate a growing number of such simulations, which we advocate should become a routine component of climate projection, and encourage international coordination of such computationally and human-resource expensive simulations as effectively as possible.

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Lili Zeng, Gengxin Chen, Ke Huang, Ju Chen, Yunkai He, Fenghua Zhou, Yikai Yang, Zhanlin Liang, Qihua Peng, Rui Shi, Tilak Priyadarshana Gamage, Rongyu Chen, Jian Li, Zhenqiu Zhang, Zewen Wu, Linghui Yu, and Dongxio Wang

Abstract

As an important part of the Indo-pacific warm pool, the Indian Ocean has great significance for research on the Asian monsoon system and global climate change. From the 1960s onwards, several international and regional programs have led to important new insights into the Indian Ocean. The eastern Tropical Indian Ocean Observation Network (TIOON) was established in 2010. The TIOON consists of two parts: large-scope observations and moored measurements. Large-scope observations are performed by the eastern tropical Indian Ocean Comprehensive Experiment Cruise (TIO-CEC). Moored measurements are executed by the TIOON mooring array and the hydrological meteorological buoy. By 2019, ten successful TIOON TIO-CEC voyages had been accomplished, making this mission the most comprehensive scientific investigation in China. The ten years of TIO-CEC voyages have collected approximately 1,006 temperature/salinity profiles, 703 GPS radiosonde profiles and numerous other observations in the Indian Ocean. To supplement the existing buoy array in the Indian Ocean, an enhanced TIOON mooring array consisting of eight sub-thermocline acoustic Doppler current profiler (ADCP) moorings, was established since 2013. The TIOON mooring equipped with both upward-looking and downward-looking WHLS75K ADCP provide valuable current monitoring information to depth of 1,000 m in the Indian Ocean. To improve air-sea interaction monitoring, two real-time hydrological meteorological buoys were launched in 2019 and 2020 in the equatorial Indian Ocean. A better understanding of the Indian Ocean requires continuous and long-term observations. The TIOON program and other aspiring field investigation programs will be promoted in the future.

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Joseph M. Prospero, Anthony C. Delany, Audrey C. Delany, and Toby N. Carlson

Abstract

There is great interest in wind-borne mineral dust because of the role that dust plays in climate by modulating solar radiation and cloud properties. Today, much research focuses on North Africa because it is Earth’s largest and most persistently active dust source. Moreover, this region is expected to be greatly impacted by climate change, which would affect dust emission rates. Interest in dust was stimulated over 50 years ago when it was discovered that African dust was frequently transported across the Atlantic in great quantities. Here we report on the initial discovery of African dust in the Caribbean Basin. We show that there were three independent “first” discoveries of African dust in the 1950s through the 1960s. In each case, the discoverers were not seeking dust but, rather, they had other research objectives. The meteorological context of African dust transport was first elucidated in 1969 with the characterization of the Saharan air layer (SAL) and its role in effecting the efficient transport of African dust over great distances to the Western Hemisphere. The link between dust transport and African climate was established in the 1970s and 1980s when dust transport to the Caribbean increased greatly following the onset of severe drought in the Sahel. Here we chronicle these events and show how they contributed to our current state of knowledge.

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Steven Caluwaerts, Sara Top, Thomas Vergauwen, Guy Wauters, Koen De Ridder, Rafiq Hamdi, Bart Mesuere, Bert Van Schaeybroeck, Hendrik Wouters, and Piet Termonia

Abstract

Today, the vast majority of meteorological data are collected in open, rural environments to comply with the standards set by the World Meteorological Organization. However, these traditional networks lack local information that would be of immense value, for example, for studying urban microclimates, evaluating climate adaptation measures, or improving high-resolution numerical weather predictions. Therefore, an urgent need exists for reliable meteorological data in other environments (e.g., cities, lakes, forests) to complement these conventional networks. At present, however, high-accuracy initiatives tend to be limited in space and/or time as a result of the substantial budgetary requirements faced by research teams and operational services. We present a novel approach for addressing the existing observational gaps based on an intense collaboration with high schools. This methodology resulted in the establishment of a regionwide climate monitoring network of 59 accurate weather stations in a wide variety of locations across northern Belgium. The project is also of large societal relevance as it bridges the gap between the youth and atmospheric science. To guarantee a sustainable and mutually valuable collaboration, the schools and their students are involved at all stages, ranging from proposing measurement locations, building the weather stations, and even data analysis. We illustrate how the approach received overwhelming enthusiasm from high schools and students and resulted in a high-accuracy monitoring network with unique locations offering novel insights.

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K. Dieter Klaes, Jörg Ackermann, Craig Anderson, Yago Andres, Thomas August, Régis Borde, Bojan Bojkov, Leonid Butenko, Alessandra Cacciari, Dorothée Coppens, Marc Crapeau, Stephanie Guedj, Olivier Hautecoeur, Tim Hultberg, Rüdiger Lang, Stefanie Linow, Christian Marquardt, Rosemarie Munro, Carlo Pettirossi, Gabriele Poli, Francesca Ticconi, Olivier Vandermarcq, Mayte Vasquez, and Margarita Vazquez-Navarro

Abstract

After successful launch in November 2018 and successful commissioning of Metop-C, all three satellites of the EUMETSAT Polar System (EPS) are in orbit together and operational. EPS is part of the Initial Joint Polar System (IJPS) with the United States (NOAA) and provides the service in the midmorning orbit. The Metop satellites carry a mission payload of sounding and imaging instruments, which allow provision of support to operational meteorology and climate monitoring, which are the main mission objectives for EPS. Applications include numerical weather prediction, atmospheric composition monitoring, and marine meteorology. Climate monitoring is supported through the generation of long time series through the program duration of 20+ years. The payload was developed and contributed by partners, including NOAA, CNES, and ESA. EUMETSAT and ESA developed the space segment in cooperation. The system has proven its value since the first satellite Metop-A, with enhanced products at high reliability for atmospheric sounding, delivered a very strong positive impact on NWP and results beyond expectations for atmospheric composition and chemistry applications. Having multiple satellites in orbit—now three—has enabled enhanced and additional products with increased impact, like atmospheric motion vector products at latitudes not accessible to geostationary observations or increased probability of radio occultations and hence atmospheric soundings with the Global Navigation Satellite System (GNSS) Radio-Occultation Atmospheric Sounder (GRAS) instruments. The paper gives an overview of the system and the embarked payload and discusses the benefits of generated products for applications and services. The conclusions point to the follow-on system, currently under development and assuring continuity for another 20+ years.

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Michelle E. Saunders and Jennifer M. Collins

Abstract

Weather information is widely available across many media platforms, including televisions, computers, smartphones, and tablets. In addition to weather forecast information, people are seeking and using a variety of weather information sources that provide them with current conditions and include tools such as satellite images and weather radar displays. However, little is known about how individuals use and perceive information from weather radar displays, despite the existence of radar since the 1940s. This study is a novel exploration of how Tampa Bay area residents use radar and identifies several important factors that influence how useful radar is perceived to be as a decision-making tool. It also investigates what information radar users find most important when choosing to view a radar display, as well as what electronic sources are used most often to access weather radar. The final goal of this study is to identify which activities motivate a Tampa Bay resident to view weather radar. Data were collected using an online survey instrument. This study finds that survey respondents in the Tampa Bay area frequently view a weather radar display and find it to be a very useful tool. Respondents who reported greater accuracy for the location of precipitation on a radar display were more likely to rate the radar display as being more useful. The majority of respondents indicate they use a smartphone device to view radar most often and that participating in outdoor activities was an important motivator for using radar.

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