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Jean-Sébastien Landry, Navin Ramankutty, and Lael Parrott

considerably from the rest of the forest for many years.) Other anthropogenic and natural disturbances, however, lead to more complex changes in spatial heterogeneity through the temporary removal of tree cover over extensive areas, followed by forest regrowth. Fire and logging are important examples of such events, which we define as stand-clearing disturbances. At the global scale, fire burns about 350 Mha yr −1 ( Giglio et al. 2013 ) and emits 1.5–3 PgC yr −1 ( Mieville et al. 2010 ; van der Werf et

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G. Strandberg and E. Kjellström

-cover changes are recognized to be an important driver of climate change on the global scale (e.g., Myhre et al. 2013 ) and even the fourth most important anthropogenic driver during the historical period ( Andrews et al. 2017 ). This, together with the relatively wide climate gradients across Europe, makes it a suitable area to study the magnitude and size of biogeophysical forcing from changing forest cover. However, the climatic effects of afforestation are still not completely understood, especially in

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Weiyue Zhang, Zhongfeng Xu, and Weidong Guo

and the extratropics via the excitation of atmospheric waves ( Schneck and Mosbrugger 2011 ). Schneck and Mosbrugger (2011) also noted that remote effects are sensitive to small initial changes, which suggests that the remote responses to land-cover change contain high uncertainties. Findell et al. (2006) argued that the extratropical response to complete tropical deforestation is difficult to distinguish from natural climate variability. In this study, we further investigate the influence of

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W. L. Ellenburg, R. T. McNider, J. F. Cruise, and John R. Christy

in the Community Climate System Model (CCSM4) from 1850 to 2100 . J. Climate , 25 , 3071 – 3095 , doi: 10.1175/JCLI-D-11-00256.1 . Leibensperger , E. M. , and Coauthors , 2012 : Climatic effects of 1950–2050 changes in US anthropogenic aerosols—Part 2: Climate response . Atmos. Chem. Phys. , 12 , 3349 – 3362 , doi: 10.5194/acp-12-3349-2012 . Li , D. , and E. Bou-Zeid , 2013 : Synergistic interactions between urban heat islands and heat waves: The impact in cities is larger than

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Andres Schmidt, Beverly E. Law, Mathias Göckede, Chad Hanson, Zhenlin Yang, and Stephen Conley

by data availability from the atmospheric mixing ratio monitoring network, that is, the total number of observations and number of observation sites. As a consequence, the degrees of freedom in the constrained flux fields need to be reduced to avoid equifinality effects as well as implausible results for parts of the model grid with low data availability. One approach is to apply aggregation to reduce the degrees of freedom (e.g., Bocquet et al. 2011 ). Multiplying the 25 920 grid cells (216

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

number of studies, there remain disparities in modeling results as to the magnitude and sometimes direction of regional and global effects ( Pitman et al. 2009 ; de Noblet-Ducoudre et al. 2012 ; Brovkin et al. 2013 ). These inconsistencies have been attributed to differences in how models parameterize albedo, how LUC is implemented, and how crop phenology and evapotranspiration is represented ( Pitman et al. 2009 ). With levels of atmospheric CO 2 expected to increase in the coming century and

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Dev Niyogi, Ming Lei, Chandra Kishtawal, Paul Schmid, and Marshall Shepherd

define the intensity of urbanization in the numerical analysis in the present study. Population and PRISM rainfall data have the same spatial grid spacing (~4 km). Note that the urban effects on rainfall are likely an aggregate of the different effects identified in literature (splitting, intensification, urban heat island–induced convection, aerosol interaction, etc.). Figure 2. (a) Example image for Indiana urban landscape from NLCD 2001 (all urban categories) and (b) Indiana population

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Keith J. Harding, Tracy E. Twine, and Yaqiong Lu

corn acreage for biofuel production ( Bagley et al. 2014 ; USDA-ERS 2014 ), the potential for expansion of second-generation biofuel crops in the region ( Bagley et al. 2014 ), and warming temperatures with anthropogenic climate change may further increase the demand for irrigation ( Döll 2002 ; Dominguez-Faus et al. 2013 ; Fischer et al. 2007 ; Vorosmarty et al. 2000 ). Because this could accelerate the depletion of the Ogallala Aquifer, it is critically important to more fully understand how

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Zhao Yang, Francina Dominguez, Hoshin Gupta, Xubin Zeng, and Laura Norman

2050 is represented as the black slash area. Domains 1 and 2 are represented as the black dash and red box. Elevations are shown in meters. Since 1970, summers in U.S. urban areas have been recorded as being progressively warmer under the synergistic effects of global warming and urban heat island effect (NCDC, http://www.ncdc.noaa.gov/cag/ ). The 2014 Climate Central report indicates that 57 out of 60 the largest U.S. cities had measurable growth in urban heat island effect over the period 2004

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Pedro Sequera, Jorge E. González, Kyle McDonald, Steve LaDochy, and Daniel Comarazamy

; Gutierrez et al. 2014) and successfully compensated the nighttime excessive cooling by adding a more complex urban parameterization that accounts for shadowing and radiation trapping effects and urban anthropogenic heat (Gutierrez et al. 2014). Figure 13. Modeled with updated land classes (red), modeled with default land classes (green), and observed (blue) hourly averaged (over the 18 METAR stations in Figure 7 for 16–26 Sep 2013): (top) 2-m air temperatures (°C) and (bottom) surface wind speeds (m s

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