To be stuck "up a river without a paddle" is an expression for a sticky situation you just can't get out of. But if that river happens to be in the northern hemisphere this summer, it's likely the paddle won't be helpful, anyway.

A painful lack of rain and relentless heat waves are drying up rivers in the US, Europe, Asia and the Middle East. Many are shrinking in length and breadth. Patches of riverbed poking out above the water are a common sight. Some rivers are so desiccated, they have become virtually impassable.

The human-caused climate crisis is fueling extreme weather across the globe, which isn't just impacting rivers, but also the people who rely on them. Most people on the planet depend on rivers in some way, whether for drinking water, to irrigate food, for energy or to ship goods. 

See how six of them look from space.

The Colorado River is drying up at its banks and thinning out, as a historic drought in the US West shows little sign of abating. The river is crucially maintained by two of the country's largest reservoirs, and to safeguard the river basin, the government has implemented mandatory water cuts and asked states to come up with additional action plans 

One of those reservoirs, Lake Mead, is shrinking in size as water levels drop toward "dead pool" status -- the point at which the reservoir won't be high enough to release water downstream through a dam. Its water levels have been on a downward trend since 2000, but have had a sharper drop since 2020. The lake has dropped so low in the past year that wild discoveries have been made, including human remains in a barrel -- a suspected homicide victim from decades ago. And the consequences of the Colorado River crisis are enormous: Around 40 million people in seven states and Mexico rely on the river's water for drinking, agriculture and electricity.The Yangtze River in Asia is drying up at its banks and its bed is emerging in some areas. But it's the Yangtze's tributaries that are already intensely parched. China has announced a nationwide drought alert for the first time in nine years, and its heat wave is its longest in six decades.

The impact of the drying Yangtze has been enormous. In Sichuan, a province of 84 million people, hydropower makes up about 80% of electricity capacity. Much of that comes from the Yangtze River, and as its flow slows down, power generation has dwindled, leaving authorities there to order all its factories shut for six days. The province is seeing around half the rain it usually does and some reservoirs have dried up entirely,according to state news agency Xinhua.

The Rhine starts in the Swiss Alps, flows through Germany and the Netherlands and then flows all the way out to the North Sea. It's a crucial channel for European shipping, but right now, it's a nightmare to navigate. 

Parts of the river's bed have emerged above the water's surface, meaning the ships that do try to pass it must weave around a series of obstacles, slowing the entire process.