Reviews & Analysis

Deciding where and how to allocate scarce funding to conserve plants and animals in a changing and uncertain climate is a thorny issue. Numerical modelling identifies the most effective mix of conservation measures based on the level of expenditure available.

The contributions of ice melt and ocean thermal expansion to sea-level rise during the last interglacial period are poorly constrained. A new quantification of their roles implies that the Antarctic ice sheet may be more sensitive to climate change than once thought.

Noxious cyanobacteria pose a considerable health threat to freshwater ecosystems. Research now suggests that toxic strains may be outcompeted by their non-toxic counterparts as surface concentrations of carbon dioxide increase.

The voluntary emission reductions pledged under the Copenhagen Accord are almost certainly insufficient to limit global warming to 2 °C. However, using the Copenhagen Green Climate Fund for mitigation efforts could achieve the reductions needed to fill the gap.

Managing climate risks to fresh waters has so far been approached by designing action plans. Now adaptation protocols are integrating knowledge of water-system vulnerabilities into more flexible strategies to keep taps running and ecosystems healthy.

The response to ocean acidification varies widely among, and even within, calcifying taxa. A study sheds light on this perplexing variability by quantifying the role of external organic layers in protecting calcified structures from corrosive sea water.

As atmospheric CO₂ increases, more plant litter is expected to enter the soil, stimulating turnover of organic matter and release of carbon. New field data show that this will intensify the terrestrial carbon cycle in the long term, and may counterbalance expected gains in carbon storage.

It is often argued that saving energy helps the environment and saves money. An analysis of three energy-saving measures shows that decisions on how the saved money is spent affect the size of the environmental benefit.

Storms that form in mid-latitude storm-track regions play a critical role in Earth's climate system. Now satellite observations indicate that changes in their location and intensity may be acting as a positive feedback to global warming.

The risk of flooding in the Netherlands could more than double by the 2040s, but the issue of who should pay for losses is an open question. Analysis reveals that private insurance could bear some — but not all — of the burden.

The abundance of some persistent organic pollutants has decreased in the Arctic atmosphere over recent years. But observations and model simulations confirm that warming is now remobilizing these toxic chemicals from sinks such as ice and sea water.

Climate impacts on agriculture are highly uncertain, leading some to question the validity of projected future crop yields. An analysis of West African agriculture shows that meaningful conclusions can be drawn from diverse crop–climate modelling results.

Climate change has reached the level of a 'scientific consensus', but is not yet a 'social consensus'. New analysis highlights that a growing divide between liberals and conservatives in the American public is a major obstacle to achieving this end.

The causes of the severe drought in the Sahel in the 1970s and 1980s are uncertain. Now a study provides the firmest evidence so far that emissions of aerosols from industrialized countries played a significant role, but other forcings cannot be ruled out yet.