Ocean acidification will result in biological winners and losers. A mesocosm experiment attached to a floatation frame and moored in clusters (pictured) in Gando Bay on the east coast of Gran Canaria shows that a toxic algal species is a winner under ocean acidification, with implications for the marine food web and, more generally, ecosystem services.

See Riebesell et al.

Snow is a key component of the climate system and is undergoing substantial changes as a consequence of anthropogenic warming. The spatial coverage and thickness of Earth’s snow cover is decreasing dramatically, with implications for water resources, atmospheric teleconnections and planetary albedo. This issue includes a Focus collection of Comments, Reviews, Perspectives and original research documenting the key role snow plays in the climate system and how this may be modified with climate change. The collection can also be found online at: nature.com/collections/snow.

Vegetation in the Windmill Islands, East Antarctica, is changing rapidly in response to a drying climate, demonstrated by changes in isotopic signatures measured along moss shoots, moss community composition and declining health. Moss, like that pictured on the cover, serves as a potentially important proxy of coastal climate change in the region.

See Robinson et al.

Elevated atmospheric CO2 (550 ppm) could cause an additional 175 million people to be zinc deficient and 122 million protein deficient (assuming 2050 population and CO2 projections) due to the reduced nutritional value of staple food crops such as wheat, rice and legumes.

See Smith and Myers

Genomic and oceanographic data show that floating debris, including rafts of living marine organisms, can cross the Southern Ocean and wash up on Antarctic beaches. Fronds of southern bull kelp (Durvillaea Antarctica, a non-Antarctic species recently found in Antarctica) floating on the surface of the ocean at Marion Island are pictured on the cover.

See Fraser et al. and Putman.

Current fossil fuel investment trends are inconsistent with the diffusion of low carbon technology, energy efficiency improvements and climate policies, which may ultimately reduce global demand for fossil fuels. Stranded fossil fuel assets could lead to a discounted global wealth loss of US$1–4 trillion, with the negative impact for producer countries amplified by climate mitigation policies of consumer countries.

See Mercure et al.

Tourism is a significant contributor to the global economy, with potentially large environmental impacts. Origin and destination accounting perspectives show that the carbon footprint of global tourism is larger than previously thought and industry decarbonization efforts are being outpaced by demand for energy-intensive travel.

See Lenzen

Rising temperatures and changing rainfall patterns lead to heat waves and droughts occurring with greater frequency and intensity. This issue includes a collection of original research documenting how droughts and heatwaves, as well as their impacts on both natural and human systems, may change with anthropogenic warming.

See Editorial

Mental health is often excluded from discussions of the impacts of climate change on human well-being. In this issue we feature a collection of papers that explore different ways in which climate change can impact mental health and highlight important directions for future research.

See Clayton, Cunsolo et al. and Berry et al.

Species’ responses to climate change are contingent on the complexity and fragmentation of their habitats. Ecological niche modelling is used to reconstruct past range shifts and identify future vulnerable areas and potential refugia of the king penguin in the Southern Ocean under climate change.

See Cristofariet al.

Methane emissions from shallow lakes may be significantly underestimated. Evidence from experimental lakes shows the combination of nutrient enrichment and warming has a synergistic effect on rates of methane bubbling.

See Davidson et al.

Ice loss from Antarctica is sensitive to changes in ice shelves, including the Ross Ice Shelf as shown on the cover. Finite-element modelling reveals that localized ice-shelf thinning, particularly in locations vulnerable to warm-water intrusion, can have far-reaching impacts across the entire shelf via tele-buttressing.

See Reese et al. and News & Views by Gagliardini.