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Sue Ellen Haupt, Branko Kosović, Scott W. McIntosh, Fei Chen, Kathleen Miller, Marshall Shepherd, Marcus Williams, and Sheldon Drobot

seeds and earth to food. Wildland fires could change all of that. Of course our understanding of these issues has greatly evolved, and this chapter treats how that understanding has progressed over the past 100 years. We now understand that the sun not only provides Earth’s energy, but also produces space weather that impacts Earth and its atmosphere. The rapid increase of available environmental data has enabled rapid advances in our understanding of processes. Similarly, advances in computational

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Keith Strong, Julia Saba, and Therese Kucera

eventual establishment of civilizations. Fig. 1. The solar atmosphere viewed in EUV light shows a wide range of magnetic structures. This composite false-color image, combining data captured by the Solar Dynamics Observatory in different filters of the Atmospheric Imaging Assembly, shows active regions (white), coronal holes (blue), and a million-km-long cold filament suspended in 1-MK plasma (red). The image was taken at 2214 UTC 2 Feb 2012. Space weather scientists research the effects of solar

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Edward C. D. Pope, David B. Stephenson, and David R. Jackson

/climate model (e.g., Arribas et al. 2011 ; MacLachlan et al. 2015 ; Swinbank et al. 2016 ), or alternatively by fitting an appropriate statistical model to past data [e.g., for solar flare forecasts ( Bloomfield et al. 2012 ); for forecasts of relativistic electrons at geostationary orbits ( Baker et al. 1990 ; Boynton et al. 2016 )]. Motivated by these needs for space weather, this study presents a novel statistical approach for issuing probabilistic forecasts of categorical events and will demonstrate

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Minda Le and V. Chandrasekar

rate. Brief algorithm descriptions are available in section 2 . The algorithm provides a surface snowfall flag (1 or 0 product) at each valid DPR Ku- and Ka-band matched footprint. Le et al. (2017) showed initial qualitative evaluations of the algorithm with promising results when compared to some of the Next Generation Weather Radars (NEXRAD; or WSR-88D). In this paper, we focus on performing more extensive ground validations in both qualitative and quantitative manner with NEXRAD, NASA

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Keith Strong, Nicholeen Viall, Joan Schmelz, and Julia Saba

The solar wind is a continuous, varying outflow of high-temperature plasma, traveling at hundreds of kilometers per second and stretching to over 100 au from the Sun. This paper is the third in a series of five papers about understanding the phenomena that cause space weather and their impacts. These papers are a primer for meteorological and climatological students who may be interested in the outside forces that directly or indirectly affect Earth’s neutral atmosphere. The series is also

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V. Venkatesh and S. J. Frasier

and thermal noise. 2. Methodology a. Considerations for SA weather radar Spaced antenna concepts have been reviewed in several works ( Briggs et al. 1950 ; Briggs 1985 ; Larsen and Röttger 1989 ; Doviak et al. 1996 ; Holloway et al. 1997 ; Zhang and Doviak 2007 ), and can be explained through the cross-correlation function of backscattered electric fields sampled by two monostatic antenna systems A 1 and A 2 separated by a baseline Δ x . For SA wind estimation, the idea is that the

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Cuong M. Nguyen and V. Chandrasekar

also contains an optimized scheduling algorithm for the PAWR, and an example of its implementation with a comparison of results to mechanically steered beam weather radar is introduced. Section 6 summarizes the main results of this work. 2. Space–time characterization model for precipitation a. Spatial scales in precipitation systems Figure 1 presents a relative scale map for different high-impact weather phenomena, exhibiting the connection between space scales and time scales. The figure shows

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Liang Zhao and Jing-Song Wang

has since remained around 680. To avoid the potential effects of this rapid change in observatory numbers, only data from the period 1958–2012 were analyzed here. The precipitation data in Fig. 1a on 5 July 2013 are derived from the China NMIC merged precipitation dataset of Chinese auto–weather station precipitation and the U.S. Climate Prediction Center morphing technique (CMORPH) precipitation product ( Pan et al. 2012 ), which includes precipitation over the East Asian continent and ocean

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Keith T. Strong, Joan T. Schmelz, Julia L. R. Saba, and Therese A. Kucera

Understanding the causes of short-term solar variability may help in developing capabilities to predict and mitigate the impacts of space weather on our increasingly technological society. Solar radiation can vary across the entire electromagnetic spectrum on time scales from seconds (flares) to decades (the solar cycle). An example of an eruptive flare, which is an event that is a combination of a flare and a coronal mass ejection (CME), is shown in Fig. 1 . F ig . 1. An X5 flare at 0046 UTC

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David Atlas and C. Laurence Korb

The spectrum of weather and climate needs for lidar observations from space is discussed. This paper focuses mainly on the requirements for winds, temperature, moisture, and pressure. Special emphasis is given to the needs for wind observations and it is shown that winds are required to depict realistically all atmospheric scales in the tropics and the smaller scales at higher latitudes, where both temperature and wind profiles are necessary. The need for means to estimate air-sea exchanges of sensible and latent heat also is noted. Lidar can aid here by measurement of the slope of the boundary layer. Recent theoretical feasibility studies concerning the profiling of temperature, pressure, and humidity by differential absorption lidar (DIAL) from space and expected accuracies are reviewed. Initial ground-based trials provide support for these approaches and also indicate their direct applicability to path-average temperature measurements near the surface. An alternative approach to Doppler lidar wind measurements also is presented. The concept involves the measurement of the displacement of the aerosol backscatter pattern, at constant height, between two successive scans of the same area, one ahead of the spacecraft and the other behind it, a few minutes later. Finally, an integrated space lidar system capable of measuring temperature, pressure, humidity, and winds which combines the DIAL methods with the aerosol pattern displacement concept is described briefly.

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