核技术如何有助于测量和适应气候变化？

The atoms of each chemical element have a characteristic number of protons, neutrons and electrons.

Atoms with the same number of protons but different number of neutrons are isotopes, which share almost the same chemical properties but differ in mass and physical properties. There are stable isotopes – they do not emit radiation – and there are unstable, radioactive isotopes.

Different nuclear techniques are used to measure the isotopes’ amounts and proportions and to trace their origin, history, sources and interactions in the environment. Through these measurements, experts can gain a better understanding of the functioning of various ecosystems.

Learn more about isotopes and their uses here.

A quarter of greenhouse gas emissions originate in agriculture, including through the release of CH₄ and N₂O – a gas 300 times more potent than CO₂ in terms of leading to global warming – from livestock and chemical fertilisers. Excess fertiliser turning into N₂O not only contributes to global warming but also pollutes soil and fresh water. Nuclear techniques are helpful to assess emissions of greenhouse gases in quantity and quality.

Isotopes can help identify the amount of fertiliser that plants take up and, therefore, reduce the amount of fertiliser applied and the volume of N₂O released.

See this article on reducing greenhouse gas emissions with nuclear techniques for more details.

Climate change has led to extremely dry conditions in many countries, making it important to understand how drought is affecting the growth of crops under these new conditions and to help find ways to save water. See why water matters.

Isotopes are used in assessing the status and movement of water in soil to understand how strong crops can be produced under changing conditions. They help communities adapt to dry conditions and successfully use cheaper and more effective methods such as drip irrigation.

By speeding up the natural process of genetic change, gamma and X-ray irradiation are used in plant mutation breeding to develop new crop varieties resistant or tolerant to drought, salinity, disease and pests. Seeds and other plant material are treated to induce genetic changes similar to spontaneous mutations, resulting in improved varieties of high yield and crops better adapted to climate changes.

Read more about the use of nuclear techniques for climate-smart agriculture.

The ocean absorbs one quarter of CO₂ released in the atmosphere, allowing 50 times more CO₂ to be stored in the ocean than in the atmosphere. Increased amounts of CO₂ lead to ocean acidification, which can affect marine organisms that are not used to acidic conditions, impacting entire ecosystems, the food chain and eventually livelihoods of communities dependent on the ocean. When the water becomes too acidic, conditions become destructive to organisms.

Nuclear and isotopic techniques are used to study the ocean and ocean acidification. They help evaluate the ocean’s capacity to store carbon, acidification’s impact on marine organisms, past changes in ocean acidity and impacts on future climate scenarios. Stable and naturally occurring radioisotopes are used to understand the cycling of carbon, including the sources and fates of organic matter.

Armed with this understanding, scientists and policy makers are in a better position to react to the changes and protect life in the ocean.   

Further information on the different techniques used to understand oceans can be found here.

Climate change affects the sources and distribution of rain worldwide, leading to changes in river flow and in the replenishment of groundwater. Isotope hydrology is used to understand how groundwater aquifers are replenished and how vulnerable they may be to climate change. This data helps protect and conserve groundwater systems.

Isotope hydrology examines the isotopic composition of hydrogen and oxygen in water. Because the isotopic makeup of water is unique with respect to the time and location of the rain from where the water originates, this technique can track where the water comes from, so its source can be protected.

Other isotopes are used to date the age of water hosted in different aquifer systems. By evaluating the age of water, scientists can understand how to best manage water supplies to ensure their long-term sustainability.

Find out more on the use of isotope hydrology.

• The IAEA uses nuclear science and technology to help countries monitor, mitigate and adapt to climate change. It gives guidance on how to preserve and restore the environment, as well as disseminate research and information to aid policy making.
• The Joint FAO/IAEA Centre of Nuclear Techniques in Food and Agriculture works to develop and further improve nuclear and isotopic techniques to intensify agricultural production and preserve natural resources, while the IAEA builds the capacity of experts around the world in the use of these techniques.
• The IAEA maintains the Ocean Acidification International Coordination Centre, advancing capacity building and global communication in ocean acidification science.
• IAEA’s Environment Laboratories use nuclear and isotopic techniques to better understand the global carbon cycle, study the ocean’s carbon storage capacity and its impacts on future climate scenarios.
• Partnering with the World Meteorological Organization, the IAEA operates the Global Network of Isotopes in Precipitation, which contains scientific advice, logistics and technical support in isotope hydrology.

To find out more about nuclear technology and its relation to climate change, read this edition of the IAEA Bulletin.