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:    Representative Concentration Pathway 6.0 (RCP6) is a pathway that describes trends in long-term, global emissions of greenhouse gases (GHGs), short-lived species, and land-use/land-cover change leading to a stabilisation of radiative forcing at 6.0 Watts per square meter (Wm −2 ) in the year 2100 without exceeding that value in prior years. Simulated with the Asia-Pacific Integrated Model (AIM), GHG emissions of RCP6 peak around 2060 and then decline through the rest of the century. The energy intensity improvement rates changes from 0.9% per year to 1.5% per year around 2060. Emissions are assumed to be reduced cost-effectively in any period through a global market for emissions permits. The exchange of CO 2 between the atmosphere and terrestrial ecosystem through photosynthesis and respiration are estimated with the ecosystem model. The regional emissions, except CO 2 and N 2 O, are downscaled to facilitate transfer to climate models. Content Type Journal Article Pages 1-18 DOI 10.1007/s10584-011-0150-5 Authors Toshihiko Masui, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan Kenichi Matsumoto, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan Yasuaki Hijioka, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan Tsuguki Kinoshita, Ibaraki University, 3-21-1 Chuo, Ami, Ibaraki 300-0393, Japan Toru Nozawa, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan Sawako Ishiwatari, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan Etsushi Kato, Japan Agency for Marine-Earth Science and Technology, 3173-25 Showa-machi, Kanazawa, Yokohama, Kanagawa 236-0001, Japan P. R. Shukla, Indian Institute of Management, Ahmedabad, Vastrapur, Ahmedabad, 380015 India Yoshiki Yamagata, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan Mikiko Kainuma, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan Journal Climatic Change Online ISSN 1573-1480 Print ISSN 0165-0009

Description:    This paper investigates changes in shoreline evolution caused by changes in wave climate. In particular, a number of nearshore wave climate scenarios corresponding to a ‘present’ (1961–1990) and a future time-slice (2071–2100) are used to drive a beach evolution model to determine monthly and seasonal statistics. To limit the number of variables, an idealised shoreline segment is adopted. The nearshore wave climate scenarios are generated from wind climate scenarios through point wave hindcast and inshore transformation. The original wind forcing comes from regional climate change model experiments of different resolutions and/or driving global climate models, representing different greenhouse-gas emission scenarios. It corresponds to a location offshore the south central coast of England. Hypothesis tests are applied to map the degree of evidence of future change in wave and shoreline statistics relative to the present. Differential statistics resulting from different global climate models and future emission scenarios are also investigated. Further, simple, fast, and straightforward methods that are capable of accommodating a great number of climate change scenarios with limited data reduction requirements are proposed to tackle the problem under consideration. The results of this study show that there are statistically significant changes in nearshore wave climate conditions and beach alignment between current and future climate scenarios. Changes are most notable during late summer for the medium-high future emission scenario and late winter for the medium-low. Despite frequent disagreement between global climate change models on the statistical significance of a change, all experiments agreed in future seasonal trends. Finally, a point of importance for coastal management, material shoreline changes are generally linked to significant changes in future wave direction rather than wave height. Content Type Journal Article Pages 1-33 DOI 10.1007/s10584-010-0011-7 Authors Anna Zacharioudaki, CIMA - Centre for Marine and Environmental Research, University of the Algarve, Hidrotec-ISE, Campus da Penha, Faro, 8005-139 Portugal Dominic E. Reeve, School of Marine Science and Engineering, University of Plymouth, Drake Circus, Plymouth, Devon PL4 8AA, UK Journal Climatic Change Online ISSN 1573-1480 Print ISSN 0165-0009