Colette's Grand Detour

Climate change is hitting Tibet especially hard, and many scientists describe the region as ‘the third pole’ because of its vast reserves of water and gases in glaciers and permafrost.

Below is a brief overview of what is being observed in Tibet:

1. Tibet is warming twice as fast as the global average. Over the last 50 years, the average temperature on the plateau has increased by 1.5-2 degrees. Winters are warmer, resulting in less snow accumulation and faster ice loss
2. Glaciers are retreating. Tibet holds the largest concentration of ice outside of the Arctic and Antarctic, but about 80% of its glaciers are retreating and some have disappeared entirely. This affects 6 of Asia’s major rivers, including the Yangtze, Mekong, Ganges, Brahmaputra, Indus and Salween, all of which rise on the plateau and provide water to over 1.5 billion people today.
3. The permafrost is thawing. 40% of the plateau is permafrost and rising temperatures are causing it to thaw. This not only destabilizes infrastructure, but more concerningly it releases trapped carbon and methane, which further amplifies warming.
4. The hydrology of the plateau is changing. Initially increased river flow is being observed as the glaciers retreat, however over time the fresh water availability is going to reduce. Water patterns are shifting with more flooding in summer affecting the barley crop and more drought in winter. And lakes are rapidly expanding, swallowing up vital farmland, resulting in food security issues.

Tibet is the ‘water tower of Asia’ and so climate change here has huge continental-level consequences. The main driver of climate change in the region is outlined below:

1. Global greenhouse gas emissions are the main driver just like everywhere else, but because Tibet is at a high altitude it is especially sensitive to warming and small changes in global averages translate to much larger local changes
2. High mountain areas like Tibet are warming faster than lowland areas – the thin atmosphere is less able to trap heat near the ground, so additional greenhouse gases have an outsized affect in the region. Snow and ice reflect sunlight, but as they melt they expose dark soil and rock which absorbs more heat (the albedo effect) creating a feedback loop.
3. Pollution from India, China and Nepal from burning biomass, coal and diesel drifts onto the plateau, darkening snow and ice and reducing reflectivity, thus accelerating melt. Dust storms from the Taklamakan desert also deposit particles that help warm glacier surfaces.
4. The Asian Monsoon is shifting which is resulting in more erratic cycles during which heavier but shorter downpours are happening causing floods and there is less consistent snowfall in the winter reducing the glaciers ability to rebuild snow layers.
5. The permafrost feedback loop is pushing more methane and CO2 into the atmosphere

So what does this all mean for the future of Tibet. Even in the low-emissions scenario of 1.5-2 degree global rise in temperatures, Tibet will experience 2-3 degrees of warming. And in the high-emission scenario (3-4 degree global rise), Tibet is expected to warm 4-6 degrees. Even in the best case scenario 20-30% of glacier volume is expected to disappear by 2050 and there will be significantly less snowpack meaning that natural water storage will reduce. In the worst case scenario, there is going to be a catastrophic collapse of the glaciers in the region.

Although initially rivers will swell as water is released as glaciers melt, by 2050, river flows will decline and downstream basins that rely on this water will dry up. This is going to trigger water insecurity, migration and cross-border tensions across South and East Asia and impact up to 2 billion people. On top of this, we will see more extreme events in the plateau. Over 1000 lakes are now considered dangerous with the potential for glacial lake outburst floods . The dry seasons will become longer in western and northern Tibet, resulting in drought. And there are projected to be heat waves.

This is a grim picture, and maybe one that not many are aware of will have such dire consequences for the world. There is a lot of discussion about what is happening in the Arctic and Antarctic but maybe there should be more discussion on the world stage about the implications if Tibet continues to rapidly warm. There is rarely anything in the news on this region.