How climate change has altered the planet’s water balance and river flows

Discussions of the impacts of climate change on the water system mostly focus on melting glaciers or rising sea levels, but not much on the rivers and lakes that provide a significant share of freshwater to human use.

River and lake systems are undergoing major changes around the world due to warming temperatures and changes in precipitation or snowfall patterns.

In some places, the flow of water in rivers is becoming increasingly abundant, and in many other places people and ecosystems are suffering desperately from the lack of water supply.

While Pakistan is facing severe flooding, there are many countries in the northern hemisphere where rivers and lakes have dried up like never before.

Due to the lack of rain and increasingly frequent heat waves, the water flows of many major rivers have reduced alarmingly from North America to Europe, from the Middle East to East Asia. Colorado’s hugely important and historically conflict-prone groundwater table has been declining for decades.

It has reached such a level that this summer the mighty Lake Mead behind the Hoover Dam almost became a dead pond. More than 40 million people depend on the Rhine, which is drying up worryingly.

There have been major changes in the world due to warming temperatures and changes in precipitation or snowfall patterns
Image Credit: Gulf News

The agreement on inland waterway transport on the Rhine was the cornerstone of the creation of the European Union.

The water levels of this river in some places in Germany have fallen to 32 centimeters, which makes it almost impossible to operate container ships. The so-called “hunger stones” have surfaced again in the Rhine in Germany and in the Elbe in the Czech Republic.

The Po River in Italy has recently seen a lot of flooding, but this summer a World War II bomb was found on its bed as the water flow nearly dried up.

France was forced to reduce the operation of some of its nuclear power plants because the water temperature of the Rhone and the Garonne was too high to be used for plant cooling purposes.

The drought has also dried up the source of the Thames in England. Many important rivers in Europe, the Danube, the Guardiana and the Loire, are also facing severe water shortages. According to the European Drought Observatory, almost half of Europe is under drought warning, and this has probably never happened in the past 500 years.

China is also experiencing record drought due to terrible heat waves. The new climate caused the drying up of several rivers in the country, including the Yangtze. The gigantic Yangtze provides more than 400 million people with drinking water and is crucial to China’s booming economy.

Decline in precipitation

Its water flows this year have halved from the average of the past five years, mainly due to a 45% drop in rainfall in the basin, creating a massive disruption to navigation and a drop in production. hydroelectric.

Sichuan Province is heavily dependent on hydroelectricity, but the water table in reservoirs is rapidly declining, leading to power rationing for thousands of factories.

Falling water levels in the Yangtze River even brought three 600-year-old Buddhist statues, which were hidden underwater, out into the open.

Growing demand for water and increasing global warming have not only caused water flow in river systems to decline, but several large freshwater lakes are also drying up.

The water masses of the Aral Sea in Central Asia, Lake Poopó in Bolivia, Lake Chad in Central Africa and Lake Owens in California have been steadily shrinking, creating a severe ecological crisis in and around these lakes and posing increasing challenges to food production, drinking water supply, trade and transportation.

Changing rainfall and excessive evaporation have dramatically reduced the water volumes of rivers and lakes in many parts of the world.

The drying up of rivers and lakes has not only harmed irrigation, navigation and industrial production; this has also led to the increased level of pollution as less water in the system fails to dilute even relatively common pollutants.

Higher pollution levels

Increased pollution and rising water temperatures in rivers and lakes are killing fish, plants and wildlife. The climate crisis has altered the climate regime, significantly affecting rivers and lakes and the people and ecosystems that depend on them.

Moreover, most of these rivers and lakes are transboundary and shared between two or more countries. Formal and informal norms and institutions have been developed between countries from the Colorado to the Rhine basin, from the Danube to the Euphrates-Tigris to the Aral Sea on water sharing.

However, these existing water-sharing mechanisms or basin-based water management institutions are proving inadequate to guide the path of freshwater cooperation, as climate change has led to an unrelenting reduction precedent of its availability.

As old river and lake water agreements come under heavy pressure, it becomes nearly impossible to sign new water-sharing agreements.

Climate change has already altered the water balance of the planet, and it has dramatically altered the flow of rivers in many parts of the world, and this will continue in the future.

This year’s drying up of rivers and lakes will not remain a year-long event; this phenomenon is likely to repeat itself more often. So the world must come together to prioritize its fight against climate change.