Heat is deadly—even in Montana. But the city of Missoula is doing something about it.

In Qatar, where temperatures have reached unbearably high degrees, an engineering professor at Qatar University has designed a way to provide air conditioning to the outdoors. Although the method is arguably not a solution for climate change and could actually have negative impacts, it is successfully allowing people in the country to be able to leave the their homes, which in turn benefits the economy of the country.

Friends of Trees, a nonprofit organization in the Portland area, are not just planting trees because they help combat climate change and improve air quality, but because they also help stop major flooding and avoid erosion. While it can be expensive to maintain the trees and clean up the leaves from storm drains, these trees could prevent millions of gallons of rainfall from flooding neighborhoods as extreme weather events are expected to increase in the future.

A housing project in Brooklyn is taking nine apartment buildings and retrofitting them to be more sustainable and cut carbon emissions. Casa Pasiva is a $20 million project that aims to reduce heating and cooling costs because of updated machinery and thick exteriors that will improve air quality. Funding for these types of initiatives is not always certain, but a collaboration between a developer and a nonprofit, with some city financing, made this first-of-a-kind green building renovation in New York possible.

With rising temperatures occurring all over the world, cities are implementing plans to combat heat waves and protect its residents. The city of Ahmedabad in India has been a model for heat resiliency after it created its first heat action plan that centered around “community-focused social measures.” Because of the plan, a 2015 heat wave resulted in fewer than 20 fatalities compared with thousands of deaths in previous years. Other cities like New York City are also participating in heat resiliency efforts aimed at protecting all of its residents.

To combat the effects of rising temperatures due to climate change, Los Angeles piloted an experiment called “cool pavements,” where they coat streets with a light-colored sealant to reflect heat. Researchers are studying how effective this method is at reducing the urban heat island effect. Using a mobile sensor station, they found mixed results: While the surface temperature of the road was cooler, a person could feel warmer on the reflective roads. Figuring out how to balance different heat-mitigating strategies could be helpful as cities like Phoenix figure out how to implement cooling infrastructure.

Researchers are using citizen science volunteers to more accurately identify hot spots in cities, where some temperatures are significantly higher than their surrounding areas. The data has also shown that there is a correlation between lower-income neighborhoods and higher temperatures. Climate change is expected to increase the number of extreme weather events, including heat waves, so mapping these urban heat islands can help cities develop new urban planning strategies.

Air pollution is a huge problem for China, but surprisingly, the Air Quality Index in several cities is improving because of a variety of experimental projects that are being rolled out and a number of clever pollution solutions from around the country.

Caltrain's $2.4 billion electrification of 51 miles of track replaced diesel trains with faster electric ones, resulting in ridership increases (it doubled on weekends) and shorter trips. This also led to an 89% reduction in riders' exposure to toxic pollution and an estimated 250,000 metric tons of annual carbon emissions reductions.

In Brazil, the world's largest producer of sugar cane, industry leaders have found a way to harvest the crop without sugar cane burning. Sugar cane burning is harmful to the environment and nearby residents. After complaints and regulations, producers invested in technology that allows them to cut the cane without burning it. This is a contrast to South Florida, despite producing less sugar cane than Brazil, producers in the state continue the practice.

New technology is helping urban planners and developers better identify which trees could help cities reduce air pollution. In Ontario, the city of Oakville adopted a new software that resulted in planners halting the planting of one type of tree after learning it had little benefit on the air quality, while another digital tool designed in London is helping citizens determine which plants help remove particulate matter.