Most current cost−benefit analyses of climate change policies suggest an optimal global climate policy that is significantly less stringent than the level required to meet the internationally agreed 2 °C target. This is partly because the sum of estimated economic damage of climate change across various sectors, such as energy use and changes in agricultural production, results in only a small economic loss or even a small economic gain in the gross world product under predicted levels of climate change. However, those cost−benefit analyses rarely take account of environmental tipping points leading to abrupt and irreversible impacts on market and nonmarket goods and services, including those provided by the climate and by ecosystems. Here we show that including environmental tipping point impacts in a stochastic dynamic integrated assessment model profoundly alters cost−benefit assessment of global climate policy. The risk of a tipping point, even if it only has nonmarket impacts, could substantially increase the present optimal carbon tax. For example, a risk of only 5% loss in nonmarket goods that occurs with a 5% annual probability at 4 °C increase of the global surface temperature causes an immediate two-thirds increase in optimal carbon tax. If the tipping point also has a 5% impact on market goods, the optimal carbon tax increases by more than a factor of 3. Hence existing cost−benefit assessments of global climate policy may be significantly underestimating the needs for controlling climate change.
Citizen science – public participation of non-scientists in scientific research – has become an important tool for monitoring and evaluating local and global environmental change. Citizen science projects have been shown to enable large-scale data collection, increase scientific literacy, and monitor environmental quality. However, few studies have examined the individual-level motivations and impacts of citizen science participation. We employ an exploratory multi-method approach (on-line surveys, a focus-group session, informal interviews, and descriptive statements) to evaluate the experiences of citizen scientists volunteering with two conservation organizations based in Bangalore, India. Our findings suggest that citizen science may contribute to increased environmental awareness among the general public. In particular, we identify a three-step process whereby highly motivated individuals, or environmental opinion leaders, seek out citizen science opportunities due to an interest in one or more environmental issues; gain expertise through citizen science participation; and diffuse acquired skills and knowledge to peers through social networks, education of other non-scientist Indian citizens, and/or changes in career or education trajectories. As a result, citizen scientists in India promote environmental principles through an active environmental advocacy network.
Understanding social-ecological system dynamics is a major research priority for sustainable management of landscapes, ecosystems and resources. But the lack of multi-decadal records represents an important gap in information that hinders the development of the research agenda. Without improved information on the long-term and complex interactions between causal factors and responses, it will be difficult to answer key questions about trends, rates of change, tipping points, safe operating spaces and pre-impact conditions. Where available long-term monitored records are too short or lacking, palaeoenvironmental sciences may provide continuous multi-decadal records for an array of ecosystem states, processes and services. Combining these records with conventional sources of historical information from instrumental monitoring records, official statistics and enumerations, remote sensing, archival documents, cartography and archaeology produces an evolutionary framework for reconstructing integrated regional histories. We demonstrate the integrated approach with published case studies from Australia, China, Europe and North America.
Projections of climate change impacts on coral reefs produced at the coarse resolution (~1°) of Global Climate Models (GCMs) have informed debate but have not helped target local management actions. Here, projections of the onset of annual coral bleaching conditions in the Caribbean under Representative Concentration Pathway (RCP) 8.5 are produced using an ensemble of 33 Coupled Model Intercomparison Project phase-5 models and via dynamical and statistical downscaling. A high-resolution (~11 km) regional ocean model (MOM4.1) is used for the dynamical downscaling. For statistical downscaling, sea surface temperature (SST) means and annual cycles in all the GCMs are replaced with observed data from the ~4-km NOAA Pathfinder SST dataset. Spatial patterns in all three projections are broadly similar; the average year for the onset of annual severe bleaching is 2040–2043 for all projections. However, downscaled projections show many locations where the onset of annual severe bleaching (ASB) varies 10 or more years within a single GCM grid cell. Managers in locations where this applies (e.g., Florida, Turks and Caicos, Puerto Rico, and the Dominican Republic, among others) can identify locations that represent relative albeit temporary refugia. Both downscaled projections are different for the Bahamas compared to the GCM projections. The dynamically downscaled projections suggest an earlier onset of ASB linked to projected changes in regional currents, a feature not resolved in GCMs. This result demonstrates the value of dynamical downscaling for this application and means statistically downscaled projections have to be interpreted with caution. However, aside from west of Andros Island, the projections for the two types of downscaling are mostly aligned; projected onset of ASB is within ±10 years for 72% of the reef locations.
A changing climate is not only a phenomenon addressing the natural world. Social aspects are also a cause of and are affected by climate change, for which reason social dynamics must be considered in climate change adaptation. Being key factors in creating and solving the challenges of climate change, end users, decision makers and local residents need to be addressed and appreciated by those seeking acceptance for adaptation measures and taking action.
In their book "Social Dimensions of Climate Change Adaptation in Coastal Regions", Grit Martinez (Ecologic Institute), Peter Fröhle and Hans-Joachim Meier address such often overlooked but key societal aspects which influence stakeholders to or not to engage in adapting to a changing climate. Hence the sociocultural and environmental dimensions of adaptation to climate change in coastal regions and beyond take centre stage in this edited volume which authors come from a wide range of disciplines embracing humanities, social and natural sciences, engineering and practitioners working in coastal regions. Bound by the German Ministry of Education and Research (Bundesministerium für Bildung und Forschung (BMBF) five year initiative KLIMZUG (“Regions adapt to climate change”), the contributions are unanimous that humans in their capacity as end-users, decision makers and local residents are key factors in creating and solving the challenges of climate change and hence are the ones who need to be addressed and appreciated when seeking acceptance and taking action.
New coastal and marine management strategies have recently been developed in many countries and regions. From an ecosystem approach perspective, the aim of such strategies is the maintenance of ecosystem integrity while enabling the sustainable use of ecosystem goods and services. There is, however, a need for harmonized definitions and standardized processes to deal not only with the interjurisdictional and multidisciplinary complexities that are associated with such strategies but also with the extensive timelines and resources implicated in the planning and implementation of these strategies. The ecosystem-based management system proposed here is based on three pillars that facilitate the integration of an ecosystem approach to coastal and oceans policy development, regardless of the ecosystem or administrative scales. The managerial pillar is based on classical risk-management systems that incorporate environmental considerations and objectives within a continuous improvement cycle of adaptive management. The managerial pillar is supported by governance structures that provide oversight and thereby ensure that planning and implementation activities adhere to modern environmental principles. The information pillar ensures that data and scientific advice are based on current knowledge, and the participation pillar brings together communication and consultation requirements as indicated by the principles of the ecosystem approach.