Where is the water that can adjust the climate on the earth? How does it regulate the climate?

Rivers are the blood vessels of the earth, conveying water and nutrients needed to maintain the earth's ecosystem, including human life. In Asia, some of the largest rivers in the world flow from the highest mountains to the vast floodplain below and finally into the ocean. Like blood vessels, these rivers connect the rocks in the mountains with the sediments on the seabed, bringing life to everything in between. Although many nutrients are essential to the survival of life, there is an element in the river that is the key to life and the future of the earth-carbon.

Dr Edward Tipper of Cambridge University studied the largest river in Asia to understand how and where carbon is transported.

"Because of the monsoon climate and high mountains, large water systems in tropical areas such as South Asia are hot spots of weathering, so they are the main areas where the atmosphere and the mainland transport carbon to the ocean. Recent research shows that this carbon transfer is not as simple as previously thought. In fact, multiple competing processes may re-release carbon dioxide into the atmosphere, "Tipper said.

Tipper and his colleagues are investigating carbon transport in Asian rivers by collecting samples from the largest rivers such as Ganges, Nujiang, Irrawaddy and Mekong.

"At the peak flow rate, the amount of carbon transported by the Mekong River per second is very close to the amount of carbon released by an ordinary family car driving 654.38 million kilometers. Understanding the carbon transfer process is crucial to understanding the future climate. "

Carbon is everywhere, and it is a complex science to understand its movement mode, emission mode or storage mode in the earth system. When natural acid rain (containing carbon dioxide dissolved in the atmosphere) dissolves minerals in rocks, carbon begins its downstream journey. This will neutralize the acid and convert the carbon dioxide in the water into bicarbonate, which will then flow into our rivers. Bicarbonate can exist in water for thousands of years-in fact, every bottle of mineral water contains bicarbonate, which you can see on the back of the ingredient label.

This chemical weathering process is one of the main ways for earth scientists to remove carbon dioxide from the atmosphere for a long time. Carbon enters the ocean through rivers, and once it enters the ocean, it will naturally be stored in deep-sea sediments for millions of years. In order to reduce the impact on the climate, we need to know how much carbon has entered the ocean, so we must know what will happen in the river.

When carbon flows downstream, different processes may affect whether it continues to flow downstream or is released into the atmosphere. Tipper said that the natural systems of these rivers are at a critical point.

Professor Robert Hilton of Durham University is committed to better understanding the feedback between carbon transfer and climate system, so as to understand how the processes on the earth's surface can inhibit (or amplify) climate change.

"Through such research projects, we can better understand how rivers recycle carbon emitted by human beings. We must find out whether climate change and river management will cause rivers to emit carbon dioxide, because this will force climate warming to be more obvious. "

As more and more carbon dioxide is emitted from burning fossil fuels, great changes have taken place in the carbon cycle and the climate of the earth is also changing. We all know that plants absorb carbon dioxide through photosynthesis, but do we all know about rivers? Rivers not only provide nutrients for our agriculture and drinking water, but also are one of the main ways to regulate the climate. Changing the direction of chemicals and rivers may have a profound impact on the way they transport carbon. No matter where we live, we all live downstream.