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Diandong Ren and Lance M. Leslie

simulate the geographical distribution of storm genesis locations as well as seasonal cycles and interannual variability of tropical cyclone frequency for the major basins (e.g., Zhao and Held 2010 ). For twenty-first-century projection, we only examine the IPCC Special Report on Emissions Scenarios (SRES) A1B emission scenario runs. 3. Methods A range of statistical techniques is employed to determine trends in TC activity. Here, TC activity is taken as mean annual frequency, and the genesis and

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Zhijuan Liu, Xiaoguang Yang, Xiaomao Lin, Kenneth G. Hubbard, Shuo Lv, and Jing Wang

substantially improved if the growing demand of food continues because of the population increases in China. Potential yield is the ceiling of the yield for a certain place, which is largely determined by the particular combination of solar radiation, temperature, soil, and plant density at a specific location ( van Ittersum and Rabbinge 1997 ). However, actual farmers’ yields in a region or country are smaller than potential yields because the latter requires nonlimiting management throughout the crop

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Mark R. Jury

−1 ) and rain (mm h −1 ) values (both with a standard deviation of ~5) for 3 successive days in three successively westward locations across the eastern Sahel (cf. Figure 1c ), such that high values refer to a convective vortex propagating westward at >10 m s −1 . Various indices to identify AEW are reviewed in Fink (2012) . The 600-hPa streamfunction over the northern Red Sea (15°–25°N, 30°–45°E) was used to further screen cases ( Spinks and Lin 2015 ), and 25 August 2009 had the highest rank

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T. F. Pinheiro, M. I. S. Escada, D. M. Valeriano, P. Hostert, F. Gollnow, and H. Müller

, with the fourth highest deforestation rate according to the last estimate ( INPE 2013 ). Approximately 14.25% (5441 km 2 ) of the forests in this county have been converted to other land-cover types ( INPE 2013 ), primarily cattle production ( IBGE 2015 ; INPE 2010 ). Figure 1. Study site location (Landsat path 227 and row 65) within the Amazon state of Pará (PA), Brazil. 3. Methodology 3.1. Landsat imagery We used Landsat Thematic Mapper (TM) images (path 227, row 65) from 1984 to 2011 to

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Peter A. Bieniek, Uma S. Bhatt, Donald A. Walker, Martha K. Raynolds, Josefino C. Comiso, Howard E. Epstein, Jorge E. Pinzon, Compton J. Tucker, Richard L. Thoman, Huy Tran, Nicole Mölders, Michael Steele, Jinlun Zhang, and Wendy Ermold

sea ice decline and general warming ( Bhatt et al. 2013 ). The Alaskan coastal tundra region is controlled by the cool summer air mass associated with the location of the sea ice ( Conover 1960 ; Cantlon 1961 ; Haugen and Brown 1980 ; Yurtsev 1994 ; Zhang et al. 1996 ; Epstein et al. 2004 ). Therefore, as Arctic sea ice has declined and surface temperatures have warmed, it is not surprising that the tundra vegetation responded with greening. Climate model simulations forced only by reduced

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Edward Armstrong, Paul Valdes, Jo House, and Joy Singarayer

Abstract

Human-induced land-use change (LUC) alters the biogeophysical characteristics of the land surface influencing the surface energy balance. The level of atmospheric CO2 is expected to increase in the coming century and beyond, modifying temperature and precipitation patterns and altering the distribution and physiology of natural vegetation. It is important to constrain how CO2-induced climate and vegetation change may influence the regional extent to which LUC alters climate. This sensitivity study uses the HadCM3 coupled climate model under a range of equilibrium forcings to show that the impact of LUC declines under increasing atmospheric CO2, specifically in temperate and boreal regions. A surface energy balance analysis is used to diagnose how these changes occur. In Northern Hemisphere winter this pattern is attributed in part to the decline in winter snow cover and in the summer due to a reduction in latent cooling with higher levels of CO2. The CO2-induced change in natural vegetation distribution is also shown to play a significant role. Simulations run at elevated CO2, yet present-day vegetation show a significantly increased sensitivity to LUC, driven in part by an increase in latent cooling. This study shows that modeling the impact of LUC needs to accurately simulate CO2-driven changes in precipitation and snowfall and incorporate accurate, dynamic vegetation distribution.

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C. Potter, S. Klooster, P. Tan, M. Steinbach, V. Kumar, and V. Genovese

ignited by lightning strikes. A major wildfire at these locations would depress NPP and result in a NEP-LO monthly anomaly. 5. Conclusions Our NASA–CASA model results reveal important patterns of geographic variability in NEP within major continental areas of the terrestrial biosphere. A unique advantage of combining ecosystem modeling with global satellite sensor drivers for vegetation cover properties is to enhance the spatial resolution of sink patterns for CO 2 in the terrestrial biosphere. On

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Yuan Zhang and George F. Hepner

–vegetation relationships are complex and spatiotemporally variant ( Pau et al. 2011 ), making it hard to predict phenology accurately across location and time. Most phenomodels use a fixed set of environmental variables and model a fixed relationship pertinent to a specific study area, limiting the applicability of phenomodels to other regions. This paper develops a short-term phenological predictive modeling framework that can be applied in regions with different physical settings to predict vegetation abundance 7

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Ademola K. Braimoh and Paul L. G. Vlek

on the type, descriptive models help to answer the following important questions ( Lambin, 1997 ). What biophysical and socioeconomic variables explain land-cover changes? At what rate does land-cover change take place? Where are the locations (likely to be) affected by change? Several descriptive modeling techniques have been used to study urbanization. One such technique is the cellular automata approach (e.g., Clarke and Gaydos, 1998 ). Cellular automata are modeling techniques in which the

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Nazzareno Diodato and Gianni Bellocchi

economic losses, and its characteristics are of importance for understanding and extrapolating the dynamics and stability of climate systems ( Pitman and Stouffer 2006 ), the dynamics and resilience of geoecosystems, and the dynamics of fluxes in hydrologic systems ( Zehe and Sivapalan 2009 ). Despite the general recognition that land degradation is a serious and widespread problem in Mediterranean countries, the same has not been quantified for many locations, and its geographical distribution and

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