Young Japanese environmental activists have installed a Climate Clock in front of Tokyo's Shibuya Station.

The clock shows the time remaining until the rise in the global average temperature reaches 1.5 degrees Celsius.

Experts warn that if global temperatures rise by 1.5 degrees above pre-industrial levels, severe weather events, such as extremely heavy rains, could spread irreversibly.

On Friday, the clock, about 10 centimeters high and 40 centimeters wide, was installed at a tourist information center near the famous statue honoring a loyal, Akita-breed dog called Hachiko.

It showed seven years and 98 days to go if greenhouse gas emissions remain at the current level.

People can learn in detail the current situation of climate change and measures taken against it through the QR code shown on the clock.

University students have collected more than 100,000 dollars in donations since they launched a crowdfunding campaign last December.

They plan to install Climate Clocks at up to 100 locations in Shibuya Ward.

One of the students, Kurobe Mutsumi, says she hopes Climate Clocks will make many people aware that climate change is an imminent crisis and think what they can do.