In their report, the scientists describe increasing aridity as the climatic and enduring condition of too little life-supporting moisture. This condition threatens the lives and livelihoods of billions across almost every region of the globe.
Drought and rising aridity are not the same
Droughts occur when there is no or too little rainfall over a longer period of time. We consider the duration of droughts to be limited and assume that a region will fully recover if sufficient rain falls afterwards (provided there is no massive destruction due to heavy rainfall and flooding).
Rising aridity is different – it is an unrelenting menace that requires lasting adaptation measures. Today, a quarter of the global population lives in drylands that are at risk of desertification. The UNCCD report finds that rising aridity is threatening people and environments in almost every global region. More than three-quarters of all land on Earth experienced a drier climate during the three decades leading up to 2020, compared to the previous 30 – year period. The total area of arid lands expanded by about 4.3 million km2 and covers now more than 40 % of global land (excluding Antarctica). People living in drylands are 2.3 billion today and models suggest as many as 5 billion could inhabit drylands in worst case climate scenario.
“The timeliness of this report—and the guidance it provides to UNCCD country Parties—can’t be overstated: It reveals rising aridity as yet another great environmental challenge of our age. This publication is an important step in understanding the scale and nature of the problem, presenting ways to mitigate and adapt to the challenge”, says Ibrahim Thiaw, Executive Secretary of UNCCD in his foreword.
Hotspots in all continents
Hotspots showing significant dryland expansion include the western United States, the Yucatan Peninsula, north-eastern Brazil, north-western Argentina, the entire Mediterranean region, the northern side of the Black Sea, the Sahel, the Rift Valley, north-eastern South Africa, the bordering area between Russia and Kazakhstan, large parts of Mongolia and north-eastern China and south-eastern Australia.
The report gives an overview of current and future trends in aridity as well as the impacts of aridity. These range from desertification to sand and dust storms, loss of biodiversity and a reduction in food production, followed by poverty and ultimately displacement.
Subsequently, aridity adaptation measures as well as policy proposals for strengthening aridity management and sustainable land use are given.