It’s a big month for climate action.
Policymakers, business leaders and citizens are converging in San Francisco this week for the Global Climate Action Summit (GCAS), which aims to boost international momentum for curbing climate change. The event will be followed by Climate Week in New York at the end of the month.
It’s a good time to reflect on what we know about climate change—both the impacts here now and those we can expect in the future. Every degree of warming will bring increasingly severe effects in the form of heat waves, drought, wildfires, flooding and storms.
Data projections give us a sense of what kinds of impacts we’ll see if greenhouse gas emissions continue unabated. Here’s a snapshot from data on Resource Watch:
Changing Water Stress
Climate change will make some places wetter and some places drier. At the same time, growing populations and economies will put additional demands on water resources.
According to WRI’s Aqueduct Water Stress Projections, 33 countries will face extremely high water stress in 2040, thanks to climate change and/or socioeconomic factors. “Extreme” water stress means that farms, businesses and other water users take up at least 80 percent of the available water supply each year. This high ratio of demand vs. supply leaves little buffer for countries to weather stressors like drought, water mismanagement and more.
More Coral Bleaching
When ocean temperatures get too warm, it can cause coral reefs to expel their colorful algae and sometimes die, an event known as bleaching. Bleaching is already a problem for coral reefs and the millions of people who rely on them for fish, storm protection and tourism revenue. But the more the oceans warm, the more bleaching occurs.
Data from WRI (displayed in the slider below) looks at the expected frequency of coral bleaching events in 2030 and 2050. By 2030 roughly half the world’s corals will likely experience extreme bleaching; by 2050, almost all of them will.
Lower Crop Yields
Climate change may also negatively affect crop yields. NASA data looks at potential climate impacts on world crop production and yields from 1970-2050. While a couple of countries will see maize yields increase in 2050—such as Brazil and Canada—the vast majority will experience reduced crop yields. Belarus is projected to face the largest of yield drop-offs, with a decrease of more than 16 percent by 2050, followed by Pakistan and Nigeria. Eastern and northern Europe will also be particularly hard hit.
Climate change will make extreme weather events more frequent and severe. Data from NASA, displayed on the map below, shows a huge uptick in the number of extreme heat days in 2051-2080, as compared to 1971-2000.
For example, Kinshasa in the Democratic Republic of the Congo experienced an average of five extreme heat days per year in 1971-2000. In 2051-2080, the city is projected to see 166 a year. New York City also experienced an average of five extreme heat days per year in 1971-2000, but is expected to have 54 a year in 2051-2080.
A warmer ocean can negatively affect fisheries and the millions of people who rely on them for food and livelihoods. The Fishery Vulnerability Index from Blasiak et. al analyzes fisheries threatened by climate change, factoring in sea surface temperature projections and socioeconomic data on countries’ reliance on fisheries and ability to adapt to climate impacts. In 2016-2050, the 10 countries whose fisheries are most threatened by climate change include Kiribati, the Federated States of Micronesia, the Solomon Islands, Maldives, Vanuatu, Samoa, Mozambique, China and Sierra Leone.