The impacts of the climate crisis will start to be deadlier than some widespread diseases like cancer as the planet continues to heat up, warns a new report from the United Nations Development Programme (UNDP).

Hotter temperatures will lead to more excess deaths, especially in parts of the world that already get very hot – likely making existing global inequalities even worse, the agency says.

But the new data also shows that by limiting how much the planet warms, we still have time to mitigate some of the potential damage.

“Concerted global progress towards Paris Agreement targets could reduce projected mortality from extreme heat in 2100 by more than 80 per cent” the report says, “potentially saving tens of millions of lives over the next decades.”

In Bangladesh, about 67 out of 100,000 people died of cancer in 2019. But that number of deaths could be dwarfed if the world continues to pump greenhouse gases like carbon dioxide into the atmosphere at a very high rate, the data shows.

By the end of the century in a high-emissions scenario, more than 130 additional people per 100,000 would die every year in Dhaka, the country’s capital and largest city. In Khulna, Bangladesh’s third-largest city, that number rises to more than 200 additional deaths per 100,000 people every year.

Higher temperatures could exacerbate deaths in many hot parts of the world, but some wealthier places could blunt the impact, the report says. In Riyadh, Saudi Arabia, while the average annual temperature could get even hotter than Dhaka or Khulna, the city would see 120 excess deaths per 100,000 people by the end of the century.

In cooler parts of the world, death rates are actually expected to fall, according to this report. In Moscow, for example, rapid warming could lead to 130 fewer deaths per 100,000 people every year by the end of the century.

The same goes for cooler parts of the US – while the death rate is likely to fall in Minneapolis, one of the coldest parts of the US, it’s likely to rise significantly in San Antonio, one of the hottest.

But worldwide, “the projected increase in death rates caused by warmer temperatures is estimated to be much larger than the projected decrease in deaths due to declines in cold days”, the report says.

Limiting future warming could lessen the death toll, the data show. In Dhaka, for example, a future with a more moderate level of greenhouse gas emissions would have about 100 fewer deaths per 100,000 people every year, compared to the high emissions scenario. And in Khulna, 150 lives per 100,000 people could be saved every year.

Some experts now say that the high emissions scenario studied in these data is, thankfully, looking less and less likely as countries turn away from fossil fuels and expand renewable energy. But those predictions also assume that countries won’t renege on any climate plans or actions in the coming decades.

Even under the more moderate scenario, however, the report still found plenty of excess deaths. And along with the danger of hotter temperatures, the climate crisis will make extreme weather like droughts, storms, wildfires and floods more common, adding additional risk to human life.

Climate scientists, politicians and policy experts from around the world will be meeting next week in Sharm el-Sheikh, Egypt for Cop27, the UN’s annual climate change conference. While attendees will attempt to make progress on global agreements to limit warming, many nations are still falling short on pledges and goals toward reducing greenhouse gas emissions.

The world is now on track to warm 2.7 degrees Celsius by the end of this century, according to the independent analysts at the Climate Action Tracker – putting the planet on course for severe climate impacts over the next few decades.