La Niña is a climate pattern that occurs when sea surface temperatures in the central and eastern tropical Pacific Ocean drop to lower-than-normal levels. During La Niña years, California can experience drought conditions due to the following reasons:
1. Decreased Rainfall: La Niña typically leads to a shift in the jet stream, causing it to move northward. This shift results in decreased rainfall in California, particularly in the winter months when the state relies on precipitation for water supply.
2. Reduced Snowpack: La Niña can also impact the snowpack in the Sierra Nevada mountains. With less precipitation falling as snow, there is a lower snowpack accumulation. This reduction in snowpack can lead to less water supply during the warmer months when the snow melts and feeds into rivers and reservoirs.
Therefore, the statement that La Niña years can cause droughts in California due to decreased rain and snow is TRUE.
