Final answer:
The Aral Sea has shrunk significantly over the last 40 years due to river diversions for irrigation, which has led to one of the planet's largest environmental disasters. While there has been some recovery in the northern part due to conservation efforts, much of the sea has become desert. The environmental impact is severe, with major losses in local ecosystems and economies.
Step-by-step explanation:
Over the past 40 years, the size of the Aral Sea has dramatically decreased. In 1960, it was the fourth largest lake in the world, with a surface area larger than West Virginia. Due to extensive irrigation projects started by the Soviet Union in the 1960s, the inflow from its two main tributary rivers, the Amu Darya and Syr Darya, was significantly reduced. This led to the Aral Sea shrinking to less than 10 percent of its original size by 2009. The eastern basin of the Aral Sea completely dried up, becoming a desert with abandoned ships scattered on the former seabed.
In the northern part, known as the Little Aral Sea, Kazakhstan has implemented conservation efforts that have seen some success. Projects like constructing a major dam have helped increase the water level and reduce salinity, giving new life to the local fishing industry. However, the southern portion, mainly in Uzbekistan, has continued to suffer, with the western portion at risk of disappearing entirely unless substantial measures are taken to replenish the water from the Amu Darya River. The desiccation of the Aral Sea is one of the most significant environmental disasters, caused entirely by human interventions.