Volume 2 Issue 7, July 2012

Australia — one of the largest per capita greenhouse-gas emitters — has committed to reduce emissions significantly over coming decades, but will its new carbon policy succeed?

Twenty-one coherent major initiatives could together stimulate sufficient reductions by 2020 to bridge the global greenhouse-gas emissions gap.

Australia's carbon pricing mechanism leads the way with innovative design in price management and revenue recycling but could fall victim to partisan politics.

The promise of a scientifically sound policy approach to tackle greenhouse-gas emissions in Australia gives hope that the country's efforts to mitigate climate change can make an effective contribution to international objectives.

Late last year, after six years of design and testing, California's Monterey Bay Aquarium Research Institute conducted the first controlled biological experiment on deep-sea animals using a Free-Ocean Carbon Dioxide Enrichment experiment. Ocean chemist Peter Brewer talks to Nature Climate Change about the project.

Despite having achieved legally binding commitments on emissions reductions, many countries have increased their appetite for carbon-intensive products, making up the difference through international trade. Anna Petherick reports on the sticky task of regulating these invisible carbon flows.

A cost-efficient use of climate funds in developing countries requires rigorous assessment of local mitigation costs. Now research presents a novel way to estimate the increase in energy costs involved in scaling up solar photovoltaic and wind power.

The pH of the ocean is expected to drop 0.3 units in the next century. This change is well within the pH range that plankton experience at present, but research suggests that changes in acidity near their cell surface could be larger.

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.

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.

Ocean pH is expected to drop by 0.3 units by 2100, but it remains unclear how plankton might respond. Now research shows that pH and carbonate chemistry at the exterior surface of marine organisms deviates increasingly from those of bulk sea water as organism metabolic activity and size increases. Understanding of such deviations is important for predicting ecological response.

Several factors can either increase or buffer the effects of climate change on the volatility of grain prices. A study shows that US corn price volatility is more sensitive to near-term climate change than to energy policy or agriculture–energy market integration. A biofuels mandate increases price sensitivity to climate change by more than 50%.

Rising carbon dioxide concentrations in oceanic waters is conventionally expected to stimulate marine primary productivity, as long as sufficient light is available. Now research shows that the combination of increased carbon dioxide and increased light exposure can negatively impact photosynthesis in marine primary producers; an effect with the potential to cause widespread declines in future marine primary productivity.

The possibility of anthropogenic ocean warming has led to a range of concerns, from impacts on fisheries and ocean acidification to rising sea level and changes in tropical cyclone frequency and intensity. This study substantially strengthens the attribution of the recently observed global ocean warming to human activity.

By combining satellite observations with global climate models, this study provides evidence that a few key equatorial islands and coral atolls could be spared the brunt of previously predicted tropical ocean warming and productivity decline, potentially providing crucial refuges for marine biodiversity amid global climate change.

A study using a newly developed framework shows how future peak temperature is related to cumulative emissions of long-lived greenhouse gases such as carbon dioxide and sustained emissions of shorter-lived species such as methane, and suggests an approach for limiting future warming to 2 °C above pre-industrial levels.

There is increasing interest in the possible impacts of wind farms on regional weather and climate. Focusing on three large wind farms located in Texas, USA, this study finds evidence for a significant warming trend at night-time and also a small warming effect at daytime over wind farms.

The discovery of an apparently universal function describing the frequency distribution for 24-h precipitation leads to a formula relating heavy precipitation to the mean amounts and the number of days when it rains. The formula has been validated using more than 30,000 daily rain-gauge records from around the world.

The 2010 Cancún Agreement established a financial mechanism, through the Green Climate Fund, to support developing countries in greenhouse-gas emissions abatement. However, the different countries’ financial needs are often assessed on the basis of top-down cost estimates of energy technologies. Now a study provides a more fine-grained bottom-up approach that highlights the need for a ‘fair’ baseline calculation methodology and calls for a phase-out of fuel subsidies.

Water management expert Arjen Hoekstra, together with environmental science and energy specialists, has analysed the impact of increasing the use of biofuels in the transport sector on global water demand.