Extreme heatwaves threaten world's food security, and other nature and climate news you need to read this week

As global "hottest-ever" limits continue to be broken, scientists warn of intensifying heat waves affecting the planet's ability to provide us with food.

July saw the world's hottest day ever recorded as Europe, the US and China experienced life-threateningly high temperatures.

Researchers predict that the growing intensity and frequency of heatwaves will cause crop failures on land and lead to ecosystems and marine life dying in the world's oceans.

"Our food system is global," John Marsham, professor of atmospheric science at Leeds University, told The Guardian. “There are growing risks of simultaneous major crop losses in different regions in the world, which will really affect food availability and prices. This is not what we’re seeing right now, but in the coming decades that’s one of the things I’m really scared of."

The nature and climate crisis could create a 12-fold increase in the frequency of heatwaves by 2040, with potentially devastating impact on global food supplies.

At sea, marine heatwaves could bring about a "silent dying" in the world's oceans, according to Daniela Schmidt, professor of earth sciences at the University of Bristol.

Rapidly rising water temperatures could decimate delicate ocean ecosystems like coral reefs, threaten fish stocks and other marine food sources, and impact the lives and livelihoods of coastal communities.

Warming temperatures are causing land and marine species to migrate to cooler climates, increasing the likelihood of depletion or extinction.

Smoke from Canada's wildfires has drifted south leaving millions of people in the US breathing poor-quality air.

Air quality advisories are in place across several states, as Air Quality Index (AQI) ratings exceeding 150 – considered "unhealthy" by the US Government – have been recorded in parts of Georgia, Tennessee, North Carolina, South Carolina, Vermont and New Hampshire.

Canada has experienced its worst wildfire season since records began, resulting in high smoke risks in Calgary, Montreal, Quebec, Toronto and other cities and regions.

As the climate crisis increases the incidents of hot, dry weather, this can fuel the spread of wildfires.

Nearly 900 wildfires are blazing with around 590 of those out of control, according to the Canadian Interagency Forest Fire Centre.

The total surface area under fire this year shows a seven-fold increase on the 10-year average for this stage of the wildfire season.

More than 10 million hectares of burned land have been recorded, equivalent to the land area of South Korea.

Climate talks between US and China produce modest progress, but goodwill between envoys John Kerry and Xie Zhenhua helped resolve recent diplomatic tensions between the two superpowers.

A charge-while-you-drive scheme will be tested in France on an electrified stretch of motorway near Paris, enabling electric vehicle owners to avoid waiting at charging stations.

A rice export ban in India could send already-high global prices soaring and exacerbate food insecurity, analysts have warned. India is the world's second-largest rice exporter after China.

Orca experts are stumped by the dramatic increase in boat bumping by killer whales, but believe their interactions with marine vessels are playful rather than malicious.

Dangerous wildfires across Greece continue as another heatwave hits. Hotter, drier and windy summers have turned the Mediterranean into a wildfire hotspot in recent years.

Bhutan floods kill seven and leave around 20 people missing as heavy rains washed away part of the 32 MW Yungichhu hydroelectric power plant. Rescue efforts are underway in the area, Reuters reports.

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