Description:    Climate change is an issue of great importance for human rights, public health, and socioeconomic equity because of its diverse consequences overall as well as its disproportionate impact on vulnerable and socially marginalized populations. Vulnerability to climate change is determined by a community’s ability to anticipate, cope with, resist, and recover from the impact of major weather events. Climate change will affect industrial and agricultural sectors, as well as transportation, health, and energy infrastructure. These shifts will have significant health and economic consequences for diverse communities throughout California. Without proactive policies to address these equity concerns, climate change will likely reinforce and amplify current as well as future socioeconomic disparities, leaving low-income, minority, and politically marginalized groups with fewer economic opportunities and more environmental and health burdens. This review explores the disproportionate impacts of climate change on vulnerable groups in California and investigates the costs and benefits of the climate change mitigation strategies specified for implementation in the California Global Warming Solutions Act of 2006 (AB 32). Lastly, knowledge gaps, future research priorities, and policy implications are identified. Content Type Journal Article Pages 1-19 DOI 10.1007/s10584-011-0310-7 Authors Seth B. Shonkoff, Department of Environmental Science, Policy, and Management, Division of Society and Environment, University of California, Berkeley, 137 Mulford Hall, MC 3144, Berkeley, CA 94720, USA Rachel Morello-Frosch, Department of Environmental Science, Policy and Management & School of Public Health, University of California, Berkeley, 137 Mulford Hall, MC 3114, Berkeley, CA 94720, USA Manuel Pastor, Departments of Geography and American Studies and Ethnicity, University of Southern California, 3620 S. Vermont Ave, KAP-462, Los Angeles, CA 90089-0255, USA James Sadd, Department of Environmental Science and Geology, Occidental College, 1600 Campus Rd., Los Angeles, CA 90041, USA Journal Climatic Change Online ISSN 1573-1480 Print ISSN 0165-0009

Description:    Globally, urban growth will add 1.5 billion people to cities by 2030, making the difficult task of urban water provisions even more challenging. In this article, we develop a conceptual framework of urban water provision as composed of three axes: water availability, water quality, and water delivery. For each axis, we calculate quantitative proxy measures for all cities with more than 50,000 residents, and then briefly discuss the strategies cities are using in response if they are deficient on one of the axes. We show that 523 million people are in cities where water availability may be an issue, 890 million people are in cities where water quality may be an issue, and 1.3 billion people are in cities where water delivery may be an issue. Tapping into groundwater is a widespread response, regardless of the management challenge, with many cities unsustainably using this resource. The strategies used by cities deficient on the water delivery axis are different than for cities deficient on the water quantity or water quality axis, as lack of financial resources pushes cities toward a different and potentially less effective set of strategies. Content Type Journal Article Pages 1-10 DOI 10.1007/s13280-011-0152-6 Authors Robert I. McDonald, Worldwide Office, The Nature Conservancy, 4245 N. Fairfax Drive, Arlington, VA 22203, USA Ian Douglas, School of Environment and Development, University of Manchester, Oxford Road, Manchester, M13 9PL UK Carmen Revenga, Worldwide Office, The Nature Conservancy, 4245 N. Fairfax Drive, Arlington, VA 22203, USA Rebecca Hale, School of Life Sciences, Arizona State University, 1711 South Rural Road, Tempe, AZ 85287, USA Nancy Grimm, Faculty of Ecology, Evolution, & Environmental Science, Arizona State University, 1711 South Rural Road, Tempe, AZ 85287, USA Jenny Grönwall, 110 Marlyn Lodge, Portsoken St, London, E1 8RB UK Balazs Fekete, CUNY Research Foundation, The City College of New York, 160 Convent Avenue, New York, NY 10031, USA Journal AMBIO: A Journal of the Human Environment Online ISSN 1654-7209 Print ISSN 0044-7447

Description:    The tree species composition of a forested landscape may respond to climate change through two primary successional mechanisms: (1) colonization of suitable habitats and (2) competitive dynamics of established species. In this study, we assessed the relative importance of competition and colonization in forest landscape response (as measured by the forest type composition change) to global climatic change. Specifically, we simulated shifts in forest composition within the Boundary Waters Canoe Area of northern Minnesota during the period 2000–2400  AD . We coupled a forest ecosystem process model, PnET-II, and a spatially dynamic forest landscape model, LANDIS-II, to simulate landscape change. The relative ability of 13 tree species to colonize suitable habitat was represented by the probability of establishment or recruitment. The relative competitive ability was represented by the aboveground net primary production. Both competitive and colonization abilities changed over time in response to climatic change. Our results showed that, given only moderate-frequent windthrow (rotation period = 500 years) and fire disturbances (rotation period = 300 years), competition is relatively more important for the short-term (〈100 years) compositional response to climatic change. For longer-term forest landscape response (〉100 years), colonization became relatively more important. However, if more frequent fire disturbances were simulated, then colonization is the dominant process from the beginning of the simulations. Our results suggest that the disturbance regime will affect the relative strengths of successional drivers, the understanding of which is critical for future prediction of forest landscape response to global climatic change. Content Type Journal Article Pages 1-31 DOI 10.1007/s10584-011-0098-5 Authors Chonggang Xu, Division of Earth and Environmental Sciences, Los Alamos National Laboratory, Los Alamos, NM 87544, USA George Z. Gertner, Department of Natural Resources & Environmental Sciences, University of Illinois, W-523 Turner Hall, MC-047, 1102 South Goodwin Ave, Urbana, IL 61801, USA Robert M. Scheller, Environmental Science and Management, Portland State University, P.O. Box 751, Portland, OR 97207, USA Journal Climatic Change Online ISSN 1573-1480 Print ISSN 0165-0009

Description:    This paper explores two issues that have been receiving increasing attention in recent decades, climate change adaptation and natural disaster risk reduction. An examination of the similarities and differences between them reveals important linkages but also significant differences, including the spectrum of threats, time and spatial scales, the importance of local versus global processes, how risks are perceived, and degree of uncertainty. Using a risk perspective to analyze these issues, preferential strategies emerge related to choices of being proactive, reactive, or emphasizing risk management as opposed to the precautionary principle. The policy implications of this analysis are then explored, using Canada as a case study. Content Type Journal Article Pages 1-15 DOI 10.1007/s10584-011-0259-6 Authors David Etkin, Disaster and Emergency Management, Faculty of Liberal Arts and Professional Studies, York University, 4700 Keele St, Toronto, Ontario, Canada M3J 1P3 J. Medalye, Political Science, Faculty of Liberal Arts & Professional Studies, York University, Toronto, Ontario, Canada K. Higuchi, Faculty of Environmental Studies, York University, Toronto, Ontario, Canada Journal Climatic Change Online ISSN 1573-1480 Print ISSN 0165-0009

Description:    Geoengineering methods are intended to reduce climate change, which is already having demonstrable effects on ecosystem structure and functioning in some regions. Two types of geoengineering activities that have been proposed are: carbon dioxide (CO 2 ) removal (CDR), which removes CO 2 from the atmosphere, and solar radiation management (SRM, or sunlight reflection methods), which reflects a small percentage of sunlight back into space to offset warming from greenhouse gases (GHGs). Current research suggests that SRM or CDR might diminish the impacts of climate change on ecosystems by reducing changes in temperature and precipitation. However, sudden cessation of SRM would exacerbate the climate effects on ecosystems, and some CDR might interfere with oceanic and terrestrial ecosystem processes. The many risks and uncertainties associated with these new kinds of purposeful perturbations to the Earth system are not well understood and require cautious and comprehensive research. Content Type Journal Article Category Review Paper Pages 1-20 DOI 10.1007/s13280-012-0258-5 Authors Lynn M. Russell, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Dr. Mail Code 0221, La Jolla, CA 92093-0221, USA Philip J. Rasch, Pacific Northwest National Laboratory, 902 Battelle Boulevard, P. O. Box 999, MSIN K9-34, Richland, WA 99352, USA Georgina M. Mace, Centre for Population Biology, Imperial College London, Ascot, Berks SL5 7PY, UK Robert B. Jackson, Nicholas School of the Environment, Duke University, Durham, NC 27708, USA John Shepherd, Earth System Science, School of Ocean and Earth Sciences, National Oceanography Centre, University of Southampton, European Way, Southampton, SO14 3ZH UK Peter Liss, School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ UK Margaret Leinen, Harbor Branch Oceanographic Institute, 5600 US Rt 1 North, Fort Pierce, FL 34946, USA David Schimel, NEON Inc, 1685 38th Street, Boulder, CO 80305, USA Naomi E. Vaughan, Tyndall Centre for Climate Change Research, School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK Anthony C. Janetos, Joint Global Change Research Institute Pacific Northwest National Laboratory/University of Maryland, 5825 University Research Court, Suite 3500, College Park, MD 20740, USA Philip W. Boyd, NIWA Centre of Chemical & Physical Oceanography, Department of Chemistry, University of Otago, Dunedin, New Zealand Richard J. Norby, Environmental Sciences Division, Oak Ridge National Laboratory, Bethel Valley Road, Bldg. 2040, MS-6301, Oak Ridge, TN 37831-6301, USA Ken Caldeira, Department of Global Ecology, Carnegie Institution, Stanford, CA 94305, USA Joonas Merikanto, Division of Atmospheric Sciences, Department of Physics, University of Helsinki, P.O Box 64, 00014 Helsinki, Finland Paulo Artaxo, Institute of Physics, University of São Paulo, Rua do Matão, Travessa R, 187, São Paulo, SP CEP 05508-090, Brazil Jerry Melillo, The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA 02543, USA M. Granger Morgan, Department of Engineering and Public Policy, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA Journal AMBIO: A Journal of the Human Environment Online ISSN 1654-7209 Print ISSN 0044-7447

Description:    Before climate change is considered in long-term coastal management, it is necessary to investigate how institutional stakeholders in coastal management conceptualize climate change, as their awareness will ultimately affect their actions. Using questionnaires in eight Baltic Sea riparian countries, this study examines environmental managers’ awareness of climate change. Our results indicate that problems related to global warming are deemed secondary to short-term social and economic issues. Respondents agree that problems caused by global warming will become increasingly important, but pay little attention to adaptation and mitigation strategies. Current environmental problems are expected to continue to be urgent in the future. We conclude that an apparent gap exists between decision making, public concerns, and scientific consensus, resulting in a situation in which the latest evidence rarely influences commonly held opinions. Content Type Journal Article Pages 645-655 DOI 10.1007/s13280-012-0327-9 Authors Joanna Piwowarczyk, Department of Marine Ecology, Institute of Oceanology, Polish Academy of Sciences, 55 Powstancow Warszawy Street, 81-712 Sopot, Poland Anders Hansson, Centre for Climate Science and Policy Research and Water and Environmental Studies, Department of Thematic Studies, Linköping University, Norrköping, Sweden Mattias Hjerpe, Centre for Climate Science and Policy Research and Water and Environmental Studies, Department of Thematic Studies, Linköping University, Norrköping, Sweden Boris Chubarenko, Atlantic Branch of the Institute of Oceanology, Russian Academy of Sciences, Kaliningrad, Russia Konstantin Karmanov, Atlantic Branch of the Institute of Oceanology, Russian Academy of Sciences, Kaliningrad, Russia Journal AMBIO: A Journal of the Human Environment Online ISSN 1654-7209 Print ISSN 0044-7447 Journal Volume Volume 41 Journal Issue Volume 41, Number 6

Description:    Although policymaking in response to the climate change threat is essentially a challenge of risk management, most studies of the relation of emissions targets to desired climate outcomes are either deterministic or subject to a limited representation of the underlying uncertainties. Monte Carlo simulation, applied to the MIT Integrated Global System Model (an integrated economic and earth system model of intermediate complexity), is used to analyze the uncertain outcomes that flow from a set of century-scale emissions paths developed originally for a study by the U.S. Climate Change Science Program. The resulting uncertainty in temperature change and other impacts under these targets is used to illustrate three insights not obtainable from deterministic analyses: that the reduction of extreme temperature changes under emissions constraints is greater than the reduction in the median reduction; that the incremental gain from tighter constraints is not linear and depends on the target to be avoided; and that comparing median results across models can greatly understate the uncertainty in any single model. Content Type Journal Article Pages 1-15 DOI 10.1007/s10584-011-0260-0 Authors Mort Webster, Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology, Cambridge, MA, USA Andrei P. Sokolov, Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology, Cambridge, MA, USA John M. Reilly, Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology, Cambridge, MA, USA Chris E. Forest, Department of Meteorology, Pennsylvania State University, University Park, PA, USA Sergey Paltsev, Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology, Cambridge, MA, USA Adam Schlosser, Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology, Cambridge, MA, USA Chien Wang, Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology, Cambridge, MA, USA David Kicklighter, The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA, USA Marcus Sarofim, AAAS Science and Technology Policy Fellow, U.S. Environmental Protection Agency, Washington DC, USA Jerry Melillo, The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA, USA Ronald G. Prinn, Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology, Cambridge, MA, USA Henry D. Jacoby, Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology, Cambridge, MA, USA Journal Climatic Change Online ISSN 1573-1480 Print ISSN 0165-0009

Description:    Under increasing water scarcity, collective groundwater management is a global concern. This article presents an interdisciplinary analysis of this challenge drawing on a survey including 50 large and small farms and gardens in a village in an agricultural land reclamation area on the edge of the Western Desert of Egypt. Findings revealed that smallholders rely on a practice of shallow groundwater use, through which drainage water from adjacent irrigation areas is effectively recycled within the surface aquifer. Expanding agroindustrial activities in the surrounding area are socio-economically important, but by mining non-renewable water in the surrounding area, they set in motion a degradation process with social and ecological consequences for all users in the multi-layered aquifer system. Based on the findings of our investigation, we identify opportunities for local authorities to more systematically connect available environmental information sources and common pool resource management precedents, to counterbalance the degradation threat. Content Type Journal Article Category Report Pages 1-14 DOI 10.1007/s13280-012-0255-8 Authors Caroline King, Oxford University Centre for the Environment, University of Oxford, South Parks Road, Oxford, UK Boshra Salem, Department of Environmental Sciences, Faculty of Science, University of Alexandria, Alexandria, Egypt Journal AMBIO: A Journal of the Human Environment Online ISSN 1654-7209 Print ISSN 0044-7447

Description:    In the last decades, due to climate changes, soil deterioration, and Land Use/Land Cover Changes (LULCCs), land degradation risk has become one of the most important ecological issues at the global level. Land degradation involves two interlocking systems: the natural ecosystem and the socio-economic system. The complexity of land degradation processes should be addressed using a multidisciplinary approach. Therefore, the aim of this work is to assess diachronically land degradation dynamics under changing land covers. This paper analyzes LULCCs and the parallel increase in the level of land sensitivity to degradation along the coastal belt of Sardinia (Italy), a typical Mediterranean region where human pressure affects the landscape characteristics through fires, intensive agricultural practices, land abandonment, urban sprawl, and tourism concentration. Results reveal that two factors mainly affect the level of land sensitivity to degradation in the study area: (i) land abandonment and (ii) unsustainable use of rural and peri-urban areas. Taken together, these factors represent the primary cause of the LULCCs observed in coastal Sardinia. By linking the structural features of the Mediterranean landscape with its functional land degradation dynamics over time, these results contribute to orienting policies for sustainable land management in Mediterranean coastal areas. Content Type Journal Article Pages 1-10 DOI 10.1007/s00267-012-9831-8 Authors S. Bajocco, Unit for Climatology and Meteorology in Agriculture (CRA-CMA), Italian National Agricultural Research Council, Via del Caravita 7a, 00186 Rome, RM, Italy A. De Angelis, Unit for Climatology and Meteorology in Agriculture (CRA-CMA), Italian National Agricultural Research Council, Via del Caravita 7a, 00186 Rome, RM, Italy L. Perini, Unit for Climatology and Meteorology in Agriculture (CRA-CMA), Italian National Agricultural Research Council, Via del Caravita 7a, 00186 Rome, RM, Italy A. Ferrara, Department of Crop Science, University of Basilicata, Via dell’Ateneo Lucano, Potenza, PZ, Italy L. Salvati, Centre for Soil-Plant Relationships (CRA-RPS), Italian National Agricultural Research Council, Via della Navicella 2-4, 00184 Rome, RM, Italy Journal Environmental Management Online ISSN 1432-1009 Print ISSN 0364-152X

Description:    Recent studies have demonstrated the geomorphic complexity and wide range of hydrologic regimes found in alpine headwater channels that provide complex habitats for aquatic taxa. These geohydrologic elements are fundamental to better understand patterns in species assemblages and indicator taxa and are necessary to aquatic monitoring protocols that aim to track changes in physical conditions. Complex physical variables shape many biological and ecological traits, including life history strategies, but these mechanisms can only be understood if critical physical variables are adequately represented within the sampling framework. To better align sampling design protocols with current geohydrologic knowledge, we present a conceptual framework that incorporates regional-scale conditions, basin-scale longitudinal profiles, valley-scale glacial macroform structure, valley segment-scale (i.e., colluvial, alluvial, and bedrock), and reach-scale channel types. At the valley segment- and reach-scales, these hierarchical levels are associated with differences in streamflow and sediment regime, water source contribution and water temperature. Examples of linked physical-ecological hypotheses placed in a landscape context and a case study using the proposed framework are presented to demonstrate the usefulness of this approach for monitoring complex temporal and spatial patterns and processes in glaciated basins. This approach is meant to aid in comparisons between mountain regions on a global scale and to improve management of potentially endangered alpine species affected by climate change and other stressors. Content Type Journal Article Pages 1-16 DOI 10.1007/s00267-012-9957-8 Authors Anne A. Weekes, Natural Systems Design, Seattle, WA, USA Christian E. Torgersen, U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, University of Washington, Seattle, WA, USA David R. Montgomery, Department of Earth and Space Sciences, Quaternary Research Center, University of Washington, Seattle, WA, USA Andrea Woodward, U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, Seattle, WA, USA Susan M. Bolton, School of Environmental and Forest Resources, University of Washington, Seattle, WA, USA Journal Environmental Management Online ISSN 1432-1009 Print ISSN 0364-152X