The Gorner Glacier in Switzerland. Its retreat has been accelerating in recent years.Source:
European Space Agency

Satellites give the visual proof of what climate change is doing to rivers and glaciers.

Climate change is distorting rain patterns across the planet, leading to drought and floods, while rising temperatures are causing glaciers to melt, according to the first ever comprehensive review of water resources by the World Meteorological Organization. The WMO says it aims to publish global water reports annually from now on in response to calls for more accurate data in an era of growing demand and limited supplies.  The State of Global Water Resources report for 2021, released on Tuesday, analyzes the effects that higher temperatures are having on the planet’s freshwater bodies. Global temperatures are now 1.1C higher than in pre-industrial times, and last year was one of the seven hottest years on record.  “The impacts of climate change are often felt through water — more intense and frequent droughts, more extreme flooding, more erratic seasonal rainfall and accelerated melting of glaciers,” said WMO Secretary-General Petteri Taalas in a statement. All these events have “cascading effects on economies, ecosystems and all aspects of our daily lives.”  About three-quarters of all natural disasters between 2001 and 2018 were water related, according to UN-Water, which coordinates the United Nations’ work on water and sanitation. At the same time, 3.6 billion people, almost half of the global population, face inadequate access to water for at least a month every year — and that number is expected to increase to over 5 billion by mid-century.  Inconsistent measurements and a lack of data collected on the ground made it hard to understand some of the effects that climate change is having on water systems, the WMO said. Researchers filled these gaps partly with modeled data and with information from satellites in NASA’s Gravity Recovery and Climate Experiment program, or GRACE, highlighting the importance of satellites and remote sensing to measure global warming.  Here’s how some of 2021’s most relevant water impacts looked from space.

bloomberg.com

Dying glaciers

Glacial melting accelerated globally in 2021. Masses of ice in Western Canada and the US and in Central Europe experienced the most significant losses over the past four decades, the WMO report shows. Running water from melting glaciers increases at first, feeding rivers and lakes nearby until it reaches a turning point that scientists call “peak water.” After that, the runoff declines and the areas depending on that water can experience drought. 

Several melting glaciers on the north slopes of the high Alaska Range feed the Tanana River, a tributary of the Yukon River. Sediment from the glaciers gives the Tanana its milky color. 
Source: European Space Agency

Widening lakes

Also known among glaciologists as the “Third Pole,” the Tibetan Plateau holds the largest reserve of freshwater outside the polar regions. The water is mostly stored in glaciers high up in the mountains. Higher temperatures are speeding their melting, shrinking the glaciers and occasionally leading to flash floods. Large amounts of water end up in mountain lakes, which are growing as a result. 

The two largest lakes west of the Tanggula Mountains have grown larger over time as glaciers thinned and shrank.
Source: NASA

Dwindling rivers

Drought in several parts of the US worsened in 2021, with the entire west of the country affected from the month of June. Discharge data from the Colorado, Missouri and Mississippi Rivers shows the amount of water they were carrying was far below normal.

Lake Powell is the second-largest reservoir by capacity in the US. Two consecutive years of intense drought have forced government water managers in the Southwest to reconsider how supplies are distributed in 2022. 
Source: NASA

In some places, the amount of water stored in land is growing — nowhere more so than in the Lake Victoria region in Africa. But overall, rivers are shrinking more than they are growing, a trend that continued in 2021. 

Lake Victoria and Lake Turkana are among the few places in the world receiving more water than the average between 1991 and 2020, according to the WMO.
Source: European Space Agency

Extreme drought

The water deficit that Iran, Iraq and Syria experienced in 2020 was intensified by a warm winter that continued in 2021. That meant lakes and reservoirs didn’t replenish ahead of the hot summer months. The resulting drought affected up to 12 million people in Iraq and Syria and 4.8 million in Iran, leading to deadly clashes in the Khuzestan province. Drought in the Horn of Africa has led to a devastating food crisis affecting 18 million. Not even intense rainfall between December 2020 to February 2021 — typically the dry season in the region — helped alleviate the situation.

The Maharloo salt lake in Iran’s desert region of Shiraz is evaporating faster than rainfall can replenish it. Depending on the time of the year, its color varies from pink to orange to red due to the organisms that thrive in its salty waters.
Source: European Space Agency

Deadly floods 

Changing weather patterns have led to unprecedented amounts of water falling in very short periods, giving rise to devastating floods. In 2021 floods in Western Europe killed 219 people, causing up to 46 billion euros in damage. Turkey, Afghanistan, India and China’s Henan province were also hit by floods that led to over 1,500 fatalities. It was a stark reminder that the effects of climate change are being felt everywhere. 

The Meuse and Roer rivers merge on the Dutch city of Roermond, near the border with Germany. In July 2021, a dam breach on the Roer contributed to extensive flooding.
Source: NASA

This is a pictorial post and I thank Peter for sending it to me.

Satellites show climate change is hurting
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