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Casey E. Davenport
,
Christian S. Wohlwend
, and
Thomas L. Koehler

throughout a semester, and do not necessarily measure deep understanding, as many exams tend to emphasize lower-order cognition ( Crooks 1988 ). The Force Concept Inventory (FCI; Hestenes et al. 1992 ), developed in the early 1990s, revealed the superficial nature of conceptual understanding of introductory physics topics by a significant proportion of college students. The application of this result dramatically shifted perceptions of the teaching and learning of physics, and subsequently radically

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Steven C. Sherwood
,
Sandrine Bony
,
Olivier Boucher
,
Chris Bretherton
,
Piers M. Forster
,
Jonathan M. Gregory
, and
Bjorn Stevens

More intensive analyses of climate simulations reveal a need to revise definitions of forcing and feedback and to recognize the new concept of rapid adjustments. The traditional and now ubiquitous framework for understanding global climate change involves an external forcing, a response whereby the climate system opposes the forcing in order to regain equilibrium, and feedbacks that amplify or damp the response ( National Research Council 2005 ). The concept is most often applied to the global

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James P. Jenrette

An objective method is developed for forecasting the occurrence and intensity of showers. A composite moisture-stability parameter is designed which approximates the current structure of the atmosphere. This parameter is then combined with a vorticity-advection parameter which dictates the changes of the current structure. The system is designed for the summer season and is tested for Chanute Air Force Base, Illinois with a resultant skill score and per cent correct of 0.74 and 90 respectively.

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Dale Barker
,
Xiang-Yu Huang
,
Zhiquan Liu
,
Tom Auligné
,
Xin Zhang
,
Steven Rugg
,
Raji Ajjaji
,
Al Bourgeois
,
John Bray
,
Yongsheng Chen
,
Meral Demirtas
,
Yong-Run Guo
,
Tom Henderson
,
Wei Huang
,
Hui-Chuan Lin
,
John Michalakes
,
Syed Rizvi
, and
Xiaoyan Zhang

model effort has had a significant data assimilation component from its earliest days. Initial discussions between major partners [NCAR, National Oceanic and Atmospheric Administration (NOAA), the U.S. Air Force Weather Agency (AFWA), Oklahoma University, and the U.S. Naval Research Laboratory] in 1999–2001 resulted in a set of generic requirements for a unified community data assimilation system: accuracy, robustness, computational efficiency, portability, flexibility, support, documentation, and

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Dongqian Wang
,
Ying Sun
,
Ting Hu
, and
Hong Yin

area under investigation. (b),(e) Time series of NHD and TAS anomalies of observations (black), CMIP6 ALL forcing simulations (red) and CMIP6 NAT forcing simulations (blue) relative to 1961–90 (thick lines denote ensemble mean, and shading denotes the 5%–95% ranges of the individual model simulations; thick dashed line denotes adjusted ensemble mean). (c) Scatterplot between NHD and TAS anomalies during the period of 1961–2022. (f) Spatial distribution of ZG500 anomalies (shaded) relative to 1961

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Fiammetta Straneo
,
Patrick Heimbach
,
Olga Sergienko
,
Gordon Hamilton
,
Ginny Catania
,
Stephen Griffies
,
Robert Hallberg
,
Adrian Jenkins
,
Ian Joughin
,
Roman Motyka
,
W. Tad Pfeffer
,
Stephen F. Price
,
Eric Rignot
,
Ted Scambos
,
Martin Truffer
, and
Andreas Vieli

An interdisciplinary and multifaceted approach is needed to understand the forcings and mechanisms behind the recent retreat and acceleration of Greenland's glaciers and its implications for future sea level rise Mass loss from the Greenland and Antarctic ice sheets tripled over the last two decades, from 100 ± 92 Gt yr −1 (0.28 ± 0.26 mm yr −1 sea level equivalent) during 1992–2000 to 298 ± 58 Gt yr −1 (0.83 ± 0.16 mm yr −1 ) during 2000–11 [see Shepherd et al. (2012) and references

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Michael K. Walters

This paper is pedagogically motivated to qualitatively demonstrate basic concepts related to Galilean invariance and partial cancellation in the individual forcing terms in the traditional form of the omega equation. The analysis provides examples of the vertical distribution of the primary quasigeostrophic (QG) forcing, showing how the individual forcing terms vary in different coordinate systems while their sum remains constant. The QG forcing is described analytically using an unstable Eady wave solution, which allows depictions of QG forcing similar to those in basic atmospheric dynamics texts. The perturbation streamfunction, temperature, and vertical velocity are seen to be invariant under change of horizontal coordinate system, while the individual magnitudes of the QG vertical motion forcing are not. The total QG forcing remains invariant in all cases and is equal to the QG forcing found from the divergence of the Q vector. The figures provided can supplement those used for traditional study and may be useful to provoke classroom discussion of related QG concepts.

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H. Stuart Muench

Forecasting severe weather conditions is a difficult problem due to both the small size and short lifetime of the storms. Conventional weather information is too coarse in time and space to follow individual storms but can indicate areas where probability of occurrence is many times higher than climatological values. Weather radars have the resolution in time and space to track severe storms, but present operational radars are not equipped to give quantitative data. Recent developments in electronics and data processing have greatly simplified the task of obtaining quantitative data, and examples are shown of work underway at Air Force Geophysics Laboratory in using digital radar to forecast small-scale convective storms. Experiments have been made in automatically tracking storms and producing guidance forecasts of severe weather probability. A difficult problem remains in developing relationships between radar measurements and intense wind, rain, and hail due to the scarcity of meteorological measurements of such unusual events.

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Anders Persson

The Coriolis force, named after French mathematician Gaspard Gustave de Coriolis (1792–1843), has traditionally been derived as a matter of coordinate transformation by an essentially kinematic technique. This has had the consequence that its physical significance for processes in the atmosphere, as well for simple mechanical systems, has not been fully comprehended. A study of Coriolis's own scientific career and achievements shows how the discovery of the Coriolis force was linked, not to any earth sciences, but to early nineteenth century mechanics and industrial developments. His own approach, which followed from a general discussion of the energetics of a rotating mechanical system, provides an alternative and more physical way to look at and understand, for example, its property as a complementary centrifugal force. It also helps to clarify the relation between angular momentum and rotational kinetic energy and how an inertial force can have a significant affect on the movement of a body and still without doing any work. Applying Coriolis's principles elucidates cause and effect aspects of the dynamics and energetics of the atmosphere, the geostrophic adjustment process, the circulation around jet streams, the meridional extent of the Hadley cell, the strength and location of the subtropical jet stream, and the phenomenon of “downstream development” in the zonal westerlies.

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Christopher W. Callahan
,
Nathaniel J. Dominy
,
Jeremy M. DeSilva
, and
Justin S. Mankin

estimates are similar in magnitude and statistically indistinguishable, supporting our conclusion that home runs increase with temperature due to reduced air density. Comparing temperature differences in climate model experiments that include greenhouse gas forcing versus those that exclude it allows us to quantify changes in home runs due to human-caused warming ( appendix , Fig. 3 ). We find that human-caused climate change decreased home runs between 1962 and 1995 and increased them thereafter

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