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Ian M. Giammanco
,
Benjamin R. Maiden
,
Heather E. Estes
, and
Tanya M. Brown-Giammanco

Abstract

The emergence of 3D scanning technologies has provided a new opportunity to explore the shape characteristics of hailstones in great detail. The ability to effectively map the shape of hailstones will improve assessments of hailstone aerodynamic properties, how their density relates to their strength, and how radar energy is scattered. Ultimately, 3D scanning of hailstones will contribute toward research in hail detection, forecasting, and damage mitigation of severe hail, which accounts for well over $1 billion in annual insured losses.

The use of a handheld 3D laser scanner in a field setting was explored during field campaigns in 2015 and 2016. Hailstones were collected following thunderstorm passages and were measured, weighed, and scanned. The system was successful in capturing 3D models of more than 40 hailstones. A full scan takes approximately 3 minutes to complete, and data can be captured at a resolution of 0.008 cm. It is believed this is the first time such a system has been used to produce 3D digital hailstone models. Analysis of the model data has shown that hailstones depart from spherical shapes as they increase in diameter, and that bulk density and strength show little correlation. While the dataset presented here is small, the use of 3D scanners in the field is a practical method to obtain detailed datasets on hailstone characteristics. In addition, these data could be used to 3D-print hailstones to explore their aerodynamics, to produce cavity molds for ice impact tests, and for modeling radar scattering properties of natural hailstone shapes.

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Neil Stenhouse
,
Allison Harper
,
Xiaomei Cai
,
Sara Cobb
,
Anne Nicotera
, and
Edward Maibach

Abstract

This article analyzes open-ended survey responses to understand how members of the American Meteorological Society (AMS) perceive conflict within the AMS over global warming. Of all survey respondents, 53% agreed that there was conflict within the AMS; of these individuals who perceived conflict, 62% saw it as having at least some productive aspects, and 53% saw at least some unproductive aspects. Among members who saw a productive side to the conflict, most agreed as to why it was productive: debate and diverse perspectives enhance science. However, among members who saw an unproductive side, there was considerable disagreement as to why. Members who are convinced of largely human-caused climate change expressed that debate over global warming sends an unclear message to the public. Conversely, members who are unconvinced of human-caused climate change often felt that their peers were closed-minded and suppressing unpopular views. These two groups converged, however, on one point: politics was seen as an overwhelmingly negative influence on the debate. This suggests that scientific organizations faced with similar conflict should understand that there may be a contradiction between legitimizing all members’ views and sending a clear message to the public about the weight of the evidence. The findings also reinforce the conclusion that attempts by scientific societies to directly address differences in political views may be met with strong resistance by many scientists.

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Jeffrey A. Hicke
,
John T. Abatzoglou
,
Steven Daley-Laursen
,
Jamie Esler
, and
Lauren E. Parker

Abstract

Climate change is often perceived as controversial in the public’s view. One meaningful way scientists can address this problem is to engage with the public to increase understanding of climate change. Attendees of scientific conferences address climate change within meetings yet rarely interact with the public as part of conference attendance. Here, we describe outreach (sending experts into the community) and inreach (bringing the public to a conference) activities at the 2015 Northwest Climate Conference in Idaho that were designed to increase the local community’s understanding of climate change and foster interaction between scientists and the public. Conference attendees volunteered to visit community schools and civic groups to give presentations and engage in a discussion on climate change. We designed a well-attended evening plenary session for the public that featured an experienced speaker who described local climate change impacts important to the community. Local high school students attended the conference, and several were mentored by conference attendees. We reached an estimated 1,000 students and 500 other members of the public in person and many others via advertising and newspaper articles. Keys to our success were local contacts with excellent connections to schools, civic organizations, local government officials, interest groups, and a pool of motivated, enthusiastic conference attendees who were already traveling to the area. We encourage other conference organizers to consider these activities in their future meetings to increase public knowledge of climate change, particularly given the urgency of action needed to limit future climate change and its impacts.

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Linda O. Mearns
,
Melissa S. Bukovsky
, and
Vanessa J. Schweizer

Abstract

In this brief article, we report the initial results of an expert elicitation with the co-PIs (regional climate modelers) of the North American Regional Climate Change Assessment Program regarding their evaluation of the relative quality of regional climate model simulations focusing on the subregion dominated by the North American monsoon (NAM). We assumed that an expert elicitation framework might reveal interesting beliefs and understanding that would be different from what would be obtained from calculating quantitative metrics associated with model quality.

The simulations considered were of six regional climate models (RCMs) that used NCEP Reanalysis 2 as boundary conditions for the years 1980–2004. The domain covers most of North America and adjacent oceans. The seven participating regional modelers were asked to complete surveys on their background beliefs about model credibility and their judgments regarding the quality of the six models based on a series of plots of variables related to the NAM (e.g., temperature, winds, humidity, moisture flux, precipitation). The specific RCMs were not identified.

We also compared the results of the expert elicitation with those obtained from using a series of metrics developed to evaluate a European collection of climate model simulations. The results proved to be quite different in the two cases.

The results of this exercise proved very enlightening regarding regional modelers’ perceptions of model quality and their beliefs about how this information should or should not be used. Based on these pilot study results, we believe a more complete study is warranted.

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Paquita Zuidema
,
Julie Haggerty
,
Maria Cadeddu
,
Jorgen Jensen
,
Emiliano Orlandi
,
Mario Mech
,
J. Vivekanandan
, and
Zhien Wang
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Nicholas T. Luchetti
,
Jessica R. P. Sutton
,
Ethan E. Wright
,
Michael C. Kruk
, and
John J. Marra

Abstract

There are more than 2,000 islands across Hawaii and the U.S.-Affiliated Pacific Islands (USAPI), where freshwater resources are heavily dependent upon rainfall. Many of the islands experience dramatic variations in precipitation during the different phases of the El Niño–Southern Oscillation (ENSO). Traditionally, forecasters in the region relied on ENSO climatologies based on spatially limited in situ data to inform their seasonal precipitation outlooks. To address this gap, a unique NOAA/NASA collaborative project updated the ENSO-based rainfall climatology for the Exclusive Economic Zones (EEZs) encompassing Hawaii and the USAPI using NOAA’s PERSIANN Climate Data Record (CDR). The PERSIANN-CDR provides a 30-yr record of global daily precipitation at 0.25° resolution (∼750 km2 near the equator). This project took place over a 10- week NASA DEVELOP National Program term and resulted in a 478-page climatic reference atlas. This atlas is based on a 30-yr period from 1 January 1985 through 31 December 2014 and complements station data by offering an enhanced spatial representation of rainfall averages.

Regional and EEZ-specific maps throughout the atlas illustrate the percent departure from average for each season based on the Oceanic Niño Index (ONI) for different ENSO phases. To facilitate intercomparisons across locations, this percentage-based climatology was provided to regional climatologists, forecasters, and outreach experts within the region. Anomalous wet and dry maps for each ENSO phase are used by the regional constituents to better understand precipitation patterns across their regions and to produce more accurate forecasts to inform adaptation, conservation, and mitigation options for drought and f looding events.

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Katie A. Wilson
,
Pamela L. Heinselman
, and
Ziho Kang

Abstract

Eye-tracking technology can observe where and how someone’s eye gaze is directed, and therefore provides information about one’s attention and related cognitive processes in real time. The use of eye-tracking methods is evident in a variety of research domains, and has been used on few occasions within the meteorology community. With the goals of Weather Ready Nation in mind, eye-tracking applications in meteorology have so far supported the need to address how people interpret meteorological information through televised forecasts and graphics. However, eye tracking has not yet been applied to learning about forecaster behavior and decision processes. In this article, we consider what current methods are being used to study forecasters and why we believe eye tracking is a method that should be incorporated into our efforts. We share our first data collection of an NWS forecaster’s eye gaze data, and explore the types of information that these data provide about the forecaster’s cognitive processes. We also discuss how eye-tracking methods could be applied to other aspects of operational meteorology research in the future, and provide motivation for further exploration on this topic.

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Russ S. Schumacher

Abstract

Floods and flash floods are, by their nature, a multidisciplinary problem: they result from a convergence of atmospheric conditions, the underlying topography, hydrological processes, and the built environment. Research aimed at addressing various aspects of floods, on the other hand, often follows paths that do not directly address all of these fundamental connections. With this in mind, the NSF-sponsored Studies of Precipitation, Flooding, and Rainfall Extremes Across Disciplines (SPREAD) workshop was organized and held in Colorado during the summers of 2013 and 2014. SPREAD brought together a group of 27 graduate students from a wide variety of academic disciplines, but with the unifying theme being research interests in extreme precipitation or flooding. During the first meeting of the workshop, groups of graduate student participants designed interdisciplinary research projects that they then began work on over the intervening year, with the second meeting providing a venue to present their results. This article will outline the preliminary findings of these research efforts. Furthermore, the workshop participants had the unique and meaningful experience of visiting several locations in Colorado that had flooded in the past, and then visiting them again in the aftermath of the devastating 2013 floods. In total, the workshop resulted in several fruitful research activities that will advance understanding of precipitation and flooding. Even more importantly, the workshop fostered the development of a network of early-career researchers and practitioners who will be “multilingual” in terms of scientific disciplines, and who are poised to lead within their respective careers and across the scientific community.

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Oscar Pizarro
,
Nadin Ramírez
,
Manuel I. Castillo
,
Ursula Cifuentes
,
Winston Rojas
, and
Matias Pizarro-Koch

Abstract

Gliders have become an efficient and reliable oceanographic platform for measuring physical and biogeochemical properties of the seawater, and the global glider fleet is rapidly expanding. In Chile, glider observations have been carried out in very different oceanographic environments, from the mild upwelling region of subtropical northern Chile to the channels of southern Patagonia. Herein, we briefly present observations and results obtained in the oxygen minimum zone off Concepcion (∼36°30′S). Many new features have been observed in this region thanks to the relatively high resolution of the glider measurements. Future plans for the glider program include an oceanic time series off central Chile that will contribute to the regional observing system of the ocean and allow evaluations of low-frequency changes like those associated with El Niño and La Niña events.

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Andreas Schiller
,
Fraser Davidson
,
Paul M. DiGiacomo
, and
Kirsten Wilmer-Becker
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