Perspectives in 2012

Carbon capture and storage is a climate mitigation technology designed to reduce emissions from fossil-fuel power plants and industrial sources. This Perspective argues that the very limited implementation of carbon capture and storage technology so far is largely the result of political, economic and social factors, rather than a technological inability to deliver.

The high levels of water extraction from the Colorado, Murray, Orange and Yellow rivers are shown to be the main cause of reduced flows in these systems. Changes in governance are urgently required to preserve the health of these rivers, especially in light of the present and future impacts of climate change.

As climate models improve, decision-makers' expectations for accurate climate predictions are growing. Natural climate variability, however, limits climate predictability and hampers the ability to guide adaptation in many regions such as North America. Scientists, policymakers and the public need to improve communication and avoid raising expectations for accurate regional predictions everywhere.

Mitigating climate change requires directed innovation efforts to develop and deploy energy technologies. An analysis of these directed efforts finds that efficient end-use technologies contribute large potential emission reductions and provide higher social returns on investment than do energy supply technologies. Yet public institutions, policies and financial resources pervasively privilege energy supply technologies.

Assessment and managment of the impacts of climate change on Earth surface systems such as glaciers, rivers and mountains are somewhat neglected in national and international climate policy initiatives. It is argued in this Perspective that this is a critical omission because Earth surface systems provide water and soil resources, sustain ecosystem services, and influence biogeochemical cycles.

Most industrialized countries import more carbon emissions, through the products they buy abroad, than they export by selling domestic products overseas, with implications for global emissions and the design of carbon trade policies. A new method unravels the determinants of these emission transfers to understand how international trade affects global emissions and the associated policy implications.

The threats posed to the marine environment by increasing atmospheric carbon dioxide are historically unprecedented, and will probably require the use of unconventional, non-passive methods to conserve marine ecosystems. In this Perspective it is argued that soliciting such approaches and evaluating their cost, safety and effectiveness must be part of a robust ocean conservation and management strategy.

This Perspective investigates the optimal properties of aerosol particles that might be considered for solar-radiation management techniques using stratospheric particle injections. The study shows that aerosol materials other than sulphuric acid are possibly better suited for potential solar-radiation management geoengineering activities aimed at mitigating global warming.

A modelling study shows that cutting greenhouse-gas emissions has the potential to stabilize global temperature increases, but predicts that sea level will continue to rise for centuries, and rapidly so, unless aggressive mitigation measures are set in place.

The main focus of adaptation strategies to reduce climate change-related hazards has been on hard-engineered structures such as sea walls, irrigation infrastructure and dams. A Perspective suggests that consideration of a broader spectrum of adaptation options is urgently needed, particularly advocating the merits of flexible, cost-effective and broadly applicable ecosystem-based adaptation approaches.

This Perspective describes techniques for quantifying uncertainties in climate projections in terms of a common framework, whereby models are used to explore relationships between past climate and climate change and future projections.

The complexity and politicization of climate computer models can hinder communication of their science, uses and limitations. Evidence suggests that information on climate models in US newspapers is declining and that when it appears, it is often within sceptic discourses. Furthermore, model projections are frequently portrayed as probably being inaccurate, and political opinion outlets provide more explanation of model results than many news sources.

Reducing carbon emissions from deforestation and degradation (REDD+) potentially provides joint solutions to climate change and biodiversity loss — a win–win situation. Based on a literature review, this study focuses on the different policy approaches available, including an assessment of their costs and benefits.

Shifts in the geographic distribution of species caused by climate change could detrimentally affect ecosystems and biodiversity. This Perspective highlights the importance of adaptations to day length in predicting the latitudinal range shifts of different species under global warming.

Complex ecological and social settings make the programme on reducing emissions through avoided deforestation, forest degradation and other forestry activities in developing countries (also known as REDD) a challenging policy to design. Research shows the advantages of a modular policy framework able to distinguish, and adequately compensate, the different outcomes of any forest carbon initiative.