Volume 8 Issue 10, October 2015

Since 1999, China's Grain for Green project has greatly increased the vegetation cover on the Loess Plateau. Now that erosion levels have returned to historic values, vegetation should be maintained but not expanded further as planned.

The United Nations' Sustainable Development Goals emphasize the importance of evidence-based decision-making. This is a clarion call for Earth scientists to contribute directly to the health, prosperity and well-being of all people.

A truly global science community for the next generation of researchers will be essential if we are to tackle Earth system sustainability. Top-down support from funders should meet bottom-up initiatives — at a pace fast enough to meet that of early-career progress.

The Moon was once thought to be depleted in volatile elements. Analyses of the carbon contents of lunar volcanic glasses reveal that carbon monoxide degassing could have produced the fire-fountain eruptions from which these glasses were formed.

Decomposition of soil organic matter could be an important positive feedback to climate change. Geochemical properties of soils can help determine what fraction of soil carbon may be protected from climate-induced decomposition.

Fires related to Amazonian deforestation are a large source of particulate matter emissions. Satellite measurements and models reveal that reductions in deforestation and fire emissions since 2001 have prevented hundreds of premature deaths each year.

Leases of land concessions in Cambodia have accelerated in the last ten years. An analysis using high-resolution maps and official documents shows that deforestation rates in the land concessions are higher than in other areas.

The volatile-rich eruptions required to produce the lunar volcanic glasses are at odds with a volatile-poor Moon. Analyses of the glasses suggest that there was enough of the volatile element carbon in the parent magmas to drive the eruptions.

Possible impact of Arctic warming on the mid-latitudes has sparked interest. Analyses of observations and climate model simulations reveal two distinct patterns of Arctic warming that affect East Asia and North America, respectively.

Land-use changes can modify regional climate patterns. A comparison of climate simulations and observations show that a large-scale irrigation scheme in East Africa inhibits rainfall over the irrigation scheme, while enhancing it further away.

Fires are used to clear tropical forests. Satellite measurements and simulations show that reductions in deforestation and associated fires in Brazil have reduced emissions of particulate matter, preventing between 400 and 1,700 deaths annually.

More than 2 million hectares of Cambodian land have been leased to investors since 2000. Combined satellite and local records show that deforestation on leased land is 29% to 105% higher than in comparable unleased areas.

Soil organic matter is a large global carbon pool. Isotopic labelling of litter in the lab and the field reveals that soil organic matter forms from labile organic compounds and litter fragments early and late in decomposition, respectively.

Rising temperature can increase soil organic matter decomposition and CO₂ emissions. In a 4,000 km north–south transect in Chile and Antarctica, soil geochemistry, which can be modified by climate, is the dominant direct control of carbon storage.

Model and proxy-based estimates of climate cooling from volcanic eruptions have disagreed. Refined simulations and tree-ring time series converge on a total of 0.8 to 1.3 °C of cooling in the Northern Hemisphere from the 1257 and 1815 eruptions.

Alpine topography in Europe has been shaped by recent glaciations. Cosmogenic dating of summits in Svalbard suggest that Arctic alpine topography is a million years old and that subsequent glaciations have preserved rather than eroded the landscape.

Magma in Earth’s crust is in a crystal-rich mushy state, yet must be fluidized before eruptions. Numerical simulations show that rapid injection of new magma into a reservoir creates a mixing bowl of fluid and crystals that are able to erupt.

Continental cores, or cratons, are thought to have been stable for billions of years. Analysis of seismic images, however, suggests that the craton root deep beneath North America may have been shifted by mantle flow.

The dynamic components of coastal water level can add metres to water levels during extreme events. A data synthesis reveals that Pacific regional wave and water level fluctuations are closely related to the El Niño/Southern Oscillation.

It is unclear how Archaean crust formed. Analysis of seismic data from Western Australia suggests that ancient crust first formed in mantle plume-like settings and later in subduction zones, possibly in response to secular cooling of the mantle.

Ice sheets expanded into the tropics at least three times in Earth's history, covering the bulk — if not all — of the globe in ice. These Snowball Earth events reflect massive and unique perturbations to the Earth's climate-carbon system. In this focus, we bring together research and opinion pieces that explore the causes and consequences of Snowball Earth glaciations.

Seventeen goals to ensure the sustainable development of the planet have been identified by the world's political leaders, and they are ready to be adopted at a Summit in New York on 25 to 27 September. The challenges encompass environmental, economic and social aspects of one overarching aim: to allow humanity to thrive without depleting the Earth's resources. We present a collection of opinion pieces and primary research articles that illustrate the enormity and range of the tasks ahead.