Blistering temperatures over the past fortnight have killed dozens of people, triggered wildfires and driven up food and electricity prices. In large areas of the Northern Hemisphere, temperature heat maps show an angry shade of red.
Heatwaves are a natural occurrence but what has happened of late is beyond normal, shattering heat records and, coupled with low rainfall, turning parched farmlands brown in many places.
Climate scientists say extreme heat is strongly correlated with climate change. What is occurring is something they have long predicted - a future of longer and more extreme heatwaves.
Japan, Greece and Sweden have been particularly badly hit of late.
WHAT RECORDS HAVE BEEN BROKEN?
In the past 30 days, there have been 2,988 new daily maximum temperatures, 153 new hottest months and 55 new record highs worldwide, according to the United States' National Oceanic and Atmospheric Administration.
In Japan, dozens of locations set record highs on Monday, and 241 individual weather stations hit at least 35 deg C. Temperatures on Monday hit a record of 41.1 deg C in the city of Kumagaya, north-west of Tokyo.
In northern Scandinavia above the Arctic Circle, temperatures reached 32 deg C last week.
Sweden has had its hottest July in 260 years, local media reported.
WHAT'S THE TREND?
The world has warmed on average about 1.1 deg C since the late 19th century.
Under the United Nations' 2015 Paris Climate Agreement, nearly 200 nations agreed to limit warming to below 2 deg C and aim for 1.5 deg C instead. But the world is far from these goals.
Reductions in emissions that nations pledged put the world on a path to warm by at least 3 deg C.
Even limiting global warming to 2 deg C will not prevent destructive and deadly climate impact as once hoped, dozens of experts concluded in a score of scientific studies released in April.
The signs are not good. Global carbon emissions hit a record high last year after three years of being flat.
Last year was also the second warmest on record, after 2016.
WHAT ARE THE RISKS?
There are many.
These include rising death rates among the elderly, the ill and the very young, especially people living in poorly insulated housing or those unable to afford electricity for air-conditioning.
In Britain, premature deaths from heatwaves could more than treble to around 7,000 a year by mid-century if the government does not act, a committee of MPs said in a report on Thursday.
In August 2003, a 10-day heatwave across Europe was thought to be the warmest in up to 500 years.
It led to more than 20,000 deaths across Europe.
In Japan, high heat and low rainfall have cut the production of lettuce, cabbage and cucumbers, and threatened water supplies to farms and cities.
The heatwave in parts of North America, Europe and Asia, coupled with a worsening drought in some areas, caused spikes in the prices of anything from wheat to electricity, Bloomberg reported.
IS CLIMATE CHANGE TO BLAME?
Scientists say climate change has greatly increased the likelihood of extremely hot summer days.
Extreme heatwaves have been rare but as the world warms, computer climate models predict they will occur more frequently.
In the latest report in 2014, the UN's Intergovernmental Panel on Climate Change said it is very likely that heatwaves will occur more often and last longer in future.
In short, the predicted extremes of weather, along with rising sea levels and melting ice caps and glaciers, are already happening and expected to get worse.