Thank you for joining us for today's Spotlight. I'm Rebekah Schipper.
And I'm Joshua Leo. Spotlight uses a special English method of broadcasting.
It is easier for people to understand, no matter where in the world they live.
Siberia. It has one of the most severe climates in the world.
This northern part of Russia makes up about 56% of the country.
And it is mostly covered with a thick layer of permafrost, or frozen earth.
Most of the lakes and rivers are frozen for much of the year.
But scientists have recently observed melting of Siberian rivers and lakes.
They are concerned. The temperatures in Siberia seem to be rising.
The scientists are especially concerned about the melting of bogs, the wetlands.
They have observed the bogs releasing methane gas as they melt.
Methane gas is similar to carbon dioxide.
Both are harmful to the environment.
Scientists have linked these gases to an increase in the effects of global warming.
One of those effects is increasing temperatures.
Clearly, rising temperatures would cause more bogs to melt.
As they melt, they will release more methane into the atmosphere. One scientist said
"If a high release rate of a harmful gas is being caused by rising temperatures that will in turn cause still higher temperatures."
This is the second program in a series about the physical signs of global warming.
People all over the world are seeing evidence of climate change.
Take a look around. Do you see any of these signs where you live?
Today's sign: the changing lives of Polar Bears.