Disminución significativa de las reservs de agua potable
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00:30Glaciers are masses of ice that form at high elevation due to snowfall, staying over the entire summer and then transforming into fern and ice and flowing downhill.
00:48So glaciers are streams of frozen water that can exist and persist at very high elevation in the mountains around the world.
01:30Glaciers take up water in cold and wet periods and they provide water in hot and dry periods.
01:40And with this role, they have the possibility to fill in lags in the water availability.
01:49This makes them very important, especially in dry regions where water is intensely used for agriculture or drinking water.
02:00Glaciers are found in all major mountain ranges around the globe.
02:25The biggest glaciers are found in Alaska and Patagonia, but also around the big ice sheets of Greenland and Antarctica.
02:33We don't count these huge ice sheets, Greenland and Antarctica, as glaciers.
02:39However, the ice caps that are around these ice sheets, they are termed glaciers.
02:45The implications of this are multifaceted, which includes the threatening of the long-term water resources.
02:52So long-term water security is really at stake here.
02:55For another just a few millions, it's literally hundreds of millions directly in the Hindu Kush-Himalaya region.
03:01It was estimated it could be up to almost two billion.
03:04And globally in the interconnected economy, it's everyone around the world who's indirectly impacted from these dramatic changes.
03:22If we look at the observed changes in the last decades, in the last century, we see that air temperature everywhere around the Earth has strongly increased,
03:45while snow precipitation is more or less stable or even on a decline.
03:51And these two factors combined, they result in increased melting of the ice and therefore a retreat of the glacier tongues into higher elevation.
04:04The biggest impact of glacier melt is the rise in global sea levels.
04:21So all the water that has been stored in the glaciers around the globe is released and is ending up in the oceans.
04:32This increase in global sea level by glacier melting isn't huge.
04:37It's a few millimeters per year.
04:40But still, when combined with tides and with flooding, this can be very important to many people around the Earth living in the coastal regions.
04:56So this is a major impact that will increase in importance in the future and will also be very long-lasting.
05:04It's not something that we will be able to stop within the next decades.
05:09So we have to be concerned about very long time periods.
05:26As glaciers retreat, we are also seeing lots of new hazards in high mountain regions.
05:48For example, outburst floods from glacial lakes, instabilities causing ice or rock avalanches.
05:58And this can be a hazard for people going to the mountains, mountaineers or hikers.
06:05But even more so for valley communities that are living at the foot of the mountains.
06:49We can mitigate the melting of glaciers by curbing CO2 emissions.
06:56This is very clear.
06:58Glaciers are responding to rising air temperatures and we can stabilize air temperatures globally with bringing CO2 emissions to zero.
07:09Many nations around the globe are attempting this, are setting goals to reduce the CO2 emissions.
07:17However, it's not fast enough at the moment.
07:38Translated by Elham Arabi