How Climate Change Is Already Affecting Earth

[Narrator] Though the planet has only warmed

by one degree celsius since the Industrial Revolution,

climate change's effect on Earth

has been anything but subtle.

2016's the hottest year on record,

setting a new high for the third year in the row.

And 2017 is expected to be just as hot.

These high temperatures

lead to an increased number of heatwaves

that can last as long as multiple months.

In 2003, a two-week heatwave in Europe

killed 23,000 people.

It was described as a once in 500 years event,

yet it happened again three years later.

Similarly devastating heatwaves happened in 2010 and 2015.

Increased evaporation rates also bring droughts,

even in areas where rain doesn't decrease.

As plants and soil lose moisture,

a larger proportion of the sun's heat goes into the air.

This creates hotter summers under drier conditions,

perfect conditions for wildfires.

Warmer air can contain more water vapor than cool air,

which leads to heavier downpours when it does rain.

This increases the odds of flash floods,

even in areas where total precipitation

is expected to decline.

There's also been a substantial increase

in Atlantic hurricane activity since the 1980s.

This is due in part to higher sea temperatures.

Ocean water is in a state of constant motion

in the form of a system of currents

known as the global conveyor belt.

These currents are largely responsible

for the regulation of the Earth's temperature.

Scientists fear the rise in ocean temperatures

could trigger catastrophically-rapid changes in climate.

As ice sheets and glaciers melt,

and as sea water warms and expands,

ocean levels rise at an alarming rate.

These rising sea levels can contaminate drinking water,

increase salinity in groundwater used for farming,

and endanger wildlife.

While there are varying viewpoints on climate change today,

one thing is clear.

Our world is changing

and we need to take action while we can.