The glacier, the largest of its kind in the Alps, is actually four smaller glaciers put together. It is part of the Jungfrau-Aletsch Protected Area, a UNESCO World Heritage Site. The glacier has been retreating, which alarms many scientists. Current estimates are that the glacier is shedding a significant part of its ice every year. Scientists have warned that the glacial expanse, the largest in western Europe, could disappear without a trace by 2100.

Melting glaciers contribute to a rise in sea level, which could threaten coastal cities and settlements around the world. Glacier melt happens naturally, but the global warming accelerated by the increase in greenhouse gas emissions since the advent of the Industrial Revolution has accelerated the rate of the melt.

The postcard was made up to 125,000 drawings and messages done by children around the world. Together, the drawings and messages measure 26,910 square feet. The messages had to do with global warming and climate change. The entirety of the drawings and messages also spelled out a message when seen from the air: STOP GLOBAL WARMING 1.5 DEGREES C.

The temperature figure is a reference to an oft-quoted figure of expected temperature rise in the near future. Global scientists used the figure prominently in a recent report sounding the alarm about the accelerating rate of global warming.

Organizing the display were Switzerland's development agency and the WAVE foundation, a conservation group that said that it now owned the Guinness World Record for most postcards making up a single image.