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Open Access Publications from the University of California

Department of Geography

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The Department offers undergraduate, M.A., and Ph.D. degrees in Geography and Geography-Environmental Studies. Research and teaching includes most major areas of human and bio-physical geography.

UCLA Geography is consistently rated as one of the top geography departments in the United States.

Department of Geography

There are 198 publications in this collection, published between 1988 and 2021.
The Alexander Von Humboldt Lectures (1)
Open Access Policy Deposits (196)

On the connection between continental-scale land surface processes and the tropical climate in a coupled ocean-atmosphere-land system

An evaluation is presented of the impact on tropical climate of continental-scale perturbations given by different representations of land surface processes (LSPs) in a general circulation model that includes atmosphere-ocean interactions. One representation is a simple land scheme, which specifies climatological albedos and soil moisture availability. The other representation is the more comprehensive Simplified Simple Biosphere Model, which allows for interactive soil moisture and vegetation biophysical processes. The results demonstrate that such perturbations have strong impacts on the seasonal mean states and seasonal cycles of global precipitation, clouds, and surface air temperature. The impact is especially significant over the tropical Pacific Ocean. To explore the mechanisms for such impact, model experiments are performed with different LSP representations confined to selected continental-scale regions where strong interactions of climate-vegetation biophysical processes are present. The largest impact found over the tropical Pacific is mainly from perturbations in the tropical African continent where convective heating anomalies associated with perturbed surface heat fluxes trigger global teleconnections through equatorial wave dynamics. In the equatorial Pacific, the remote impacts of the convection anomalies are further enhanced by strong air-sea coupling between surface wind stress and upwelling, as well as by the effects of ocean memory. LSP perturbations over South America and Asia-Australia have much weaker global impacts. The results further suggest that correct representations of LSP, land use change, and associated changes in the deep convection over tropical Africa are crucial to reducing the uncertainty of future climate projections with global climate models under various climate change scenarios. © 2013 American Meteorological Society.

Impacts of Trade on Wage Inequality in Los Angeles: Analysis Using Matched Employer-Employee Data

Over the past twenty-five years, earnings inequality has risen dramatically in the US, reversing trends of the preceding half-century. Growing inequality is closely tied to globalization and trade through the arguments of Heckscher-Ohlin. However, with few exceptions, empirical studies fail to show that trade is the primary determinant of shifts in relative wages. We argue that lack of empirical support for the trade-inequality connection results from the use of poor proxies for worker skill and the failure to control for other worker characteristics and plant characteristics that impact wages. We remedy these problems by developing a matched employee-employer database linking the Decennial Household Census (individual worker records) and the Longitudinal Research Database (individual manufacturing establishment records) for the Los Angeles CMSA in 1990 and 2000. Our results show that trade has a significant impact on wage inequality, pushing down the wages of the less-skilled while allowing more highly skilled workers to benefit from exports. That impact has increased through the 1990s, swamping the influence of skill-biased technical change in 2000. Further, the negative effect of trade on the wages of the less-skilled has moved up the skill distribution over time. This suggests that over the long-run, increasing levels of education may not insulate more skilled workers within developed economies from the impacts of trade.

Stem-root flow effect on soil–atmosphere interactions and uncertainty assessments

Abstract. Soil water can rapidly enter deeper layers via vertical redistribution of soil water through the stem–root flow mechanism. This study develops the stem–root flow parameterization scheme and coupled this scheme with the Simplified Simple Biosphere model (SSiB) to analyze its effects on land–atmospheric interactions. The SSiB model was tested in a single column mode using the Lien Hua Chih (LHC) measurements conducted in Taiwan and HAPEX-Mobilhy (HAPEX) measurements in France. The results show that stem–root flow generally caused a decrease in the moisture content at the top soil layer and moistened the deeper soil layers. Such soil moisture redistribution results in significant changes in heat flux exchange between land and atmosphere. In the humid environment at LHC, the stem–root flow effect on transpiration was minimal, and the main influence on energy flux was through reduced soil evaporation that led to higher soil temperature and greater sensible heat flux. In the Mediterranean environment of HAPEX, the stem–root flow significantly affected plant transpiration and soil evaporation, as well as associated changes in canopy and soil temperatures. However, the effect on transpiration could either be positive or negative depending on the relative changes in the moisture content of the top soil vs. deeper soil layers due to stem–root flow and soil moisture diffusion processes.

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Recent Works (1)

Empire’s labor: the global army that supports U.S. wars

In a dramatic unveiling of the little-known world of contracted military logistics, Adam Moore examines the lives of the global army of laborers who support US overseas wars. Empire's Labor brings us the experience of the hundreds of thousands of men and women who perform jobs such as truck drivers and administrative assistants at bases located in warzones in the Middle East and Africa. He highlights the changes the US military has undergone since the Vietnam War, when the ratio of contractors to uniformed personnel was roughly 1:6. In Afghanistan it has been as high as 4:1. This growth in logistics contracting represents a fundamental change in how the US fights wars, with the military now dependent on a huge pool of contractors recruited from around the world. It also, Moore demonstrates, has social, economic, and political implications that extend well beyond the battlefields.

Focusing on workers from the Philippines and Bosnia, two major sources of "third country national" (TCN) military labor, Moore explains the rise of large-scale logistics outsourcing since the end of the Cold War; describes the networks, infrastructures, and practices that span the spaces through which people, information, and goods circulate; and reveals the experiences of foreign workers, from the hidden dynamics of labor activism on bases, to the economic and social impacts these jobs have on their families and the communities they hail from. Through his extensive fieldwork and interviews, Moore gives voice to the agency and aspirations of the many thousands of foreigners who labor for the US military.