Glaciers, or Jöklar, are important indicators of the health of the planet. As the Earth's atmosphere warms, glaciers are melting at an increasing rate, a clear sign of the impacts of climate change. Glaciers provide a natural form of climate control, reflecting sunlight to keep the Earth's surface cool. They play a vital role in the Earth's water cycle, helping to regulate the flow of water and maintain a stable water supply. 

Iceland's glaciers have been shrinking rapidly in recent decades due to climate change. Europe's largest glacier, Vatnajökull, has been losing an average of 11 billion tons of ice per year since the 1990s. That's equivalent to a loss of 1% of its mass per year. The rate of melting has been increasing in recent years, and it is expected to continue to accelerate unless urgent action is taken to reduce greenhouse gas emissions. 

Okjökull, also known as "Ok" glacier, was a small glacier located in western Iceland. It was declared officially extinct in 2014, after losing over 95% of its mass due to melting caused by rising temperatures. Okjökull's demise is a clear example of the effects of climate change on glaciers around the world, with many of them expected to completely disappear within the next few decades.