Climate change impacts - environmental, social, biodiversity and ice

Climate change impacts

Using new analysis for the upper 2 thousand metres of the world’s oceans, it was found that ocean temperatures were at a record high in 2018. The last five years have been the hottest ocean temperatures on record.  Ocean warming has been accelerating since the 1990s.

Ocean warming is faster than predicted. More than 90 percent of heat trapped by greenhouse gas emissions accumulates in the ocean. Scientists found agreement among multiple lines of temperature measurements that the world’s oceans have been warming about 40 percent faster than the Intergovernmental Panel on Climate Change estimated in the Fifth Assessment Report of 2014.

Social and Environmental

Warming to affect your morning coffee: Studying the extinction risk to wild coffee species, it has been found that at least 60 percent of all coffee species are threatened with extinction. They find that although there are several risks to coffee varieties, including disease and deforestation, climate is a significant threat given projections of longer droughts and the spread of pathogens. If these wild varieties of coffee disappear, it may be more challenging for scientists to create new varieties that can adapt to a warming, drier planet.

Climate played a role in asylum applications: Examining data on asylum applications for 157 countries, it has been found that climatic conditions contributes to more severe drought and greater armed conflict, and was associated with asylum applications between 2011 and 2015. This was particularly true for western Asian and northern African countries in 2010-2012, which were experiencing political transformations associated with the Arab Spring.

Plants’ absorb less carbon dioxide: As a result of climate-induced changes in soil moisture, the land carbon sink will be reduced. They suggest that any increase in carbon uptake due to carbon fertilisation may not continue in the second half of the century, resulting in a rapid rise in carbon dioxide concentrations.

Warming and heart defects in babies: Studying various regions of the United States, it was found that that maternal exposure to heat during the early stages of pregnancy may contribute to a rise in congenital heart defects. The authors say that heat exposure during the early weeks of pregnancy can lead to foetal cell death or interfere with protein synthesis.


Seals, whales and penguins prefer the cold: Surprisingly, species diversity of marine mammals and birds is greatest when seas are cold in temperate latitudes (unlike other species which tend to have greater diversity in the tropics). In a new study, researchers have established a theory why this is the case: they find that birds and warm-blooded predators (such as whales and seals) are more alert in the colder waters and their cold-blooded prey (such as fish) can be sluggish, giving them a hunting advantage. They note that rising ocean temperatures could have negative impacts on mammal and bird populations, changing the balance of species across the globe.

Krill migrating south: Researchers have found that the distribution of krill, which forms the base of the food chain, has declined in their northern ranges in the past 90 years, and populations are becoming more concentrated towards Antarctica in response to warming waters. The authors note that the changing distribution is already affecting the food web.


Antarctic sea ice already has a bad record for 2019: It had been documented that Antarctic sea ice extent was only 5.5 million km2 on January 1, 2019. This is the lowest extent of sea ice on that date for the 40-year old satellite record. They also found that the rate of ice extent loss for December 2018 was the fastest in the satellite record.

Six-fold increase in Antarctic ice loss: Using satellite record data, it is estimated that ice mass loss from the Antarctic Ice Sheet has rapidly accelerated over the last four decades – from roughly 40 billion tons per year in 1979–1990 to about 252 billion tons a year in 2009–2017. The ice loss was greatest where there was an influx of warm waters. The scientists estimate the contribution of Antarctic ice to global sea level rise averaged 3.6 mm per decade with a cumulative 14 mm since 1979. The researchers warn that there could be more ice shelves exposed to warm waters than previously thought, especially in East Antarctica, which could contribute multimetre sea level rise if climate change continues unabated.

Beneath the surface of Thwaites Glacier: The Thwaites Glacier in the Antarctic Ice Sheet is prone to rapid retreat and is a significant contributor to sea level rise. Researchers have now found a large underwater cavity,  two-thirds the size of Manhattan, which used to contain 14 billion tons of ice, but much of it has melted in just three years. The presence of a cavity like this allows for warm waters to get further under the glacier. The scientists suggest that models are underestimating how quickly the glacier is losing ice. 

Methane from Greenland’s melt: Methane is a greenhouse gas 28 times more powerful at trapping heat than carbon dioxide. Scientists have now found that methane being produced below the Greenland ice sheet -- from inorganic and ancient organic carbon buried beneath the ice -- is being released into the water during the melt season. The authors suggest that methane leaks from glacier melt have been underappreciated and should be incorporated into efforts to estimate Earth’s methane budget.

Loss of ice cover on lakes: To date there has not been a comprehensive large-scale assessment of ice loss of lakes. Researchers have now documented 14,800 lakes that are vulnerable to ice-free winters in the Northern Hemisphere. This number climbs to 35,300 with 2˚C of warming, impacting up to 400 million people, given their reliance on the ice for fish harvest, transportation, recreation, cultural traditions and other services.