GOLDEN VALLEY, Minn. — Scientists and environmental advocates will gather August 18 atop the former Okjökull glacier in Iceland. They'll be there to memorialize a glacier that melted as a result of climate change. 

The before and after pictures (pictured: 1986 & 2019, courtesy: NASA) are dramatic. This glacier, of course, is just one of many around the world that are shrinking or considered extinct. 

Scientists consider a glacier 'dead' when it no longer advances, meaning there's no longer enough snowfall to keep the glacier moving and the volume of ice moving downward or outward.

Sea ice is also at a critical low point across much of the arctic this summer.