Western Mega-Drought Worst in over 1200 Years!
The current state of the West appears to be a truly historic one. The extreme water shortages, wild fires and overall dryness are unprecedented. According to new research, the US Western mega-drought is the driest in recorded history, that’s over 1200 years. The South Western US is going through a drought that started at the tip of the century. Based on the research, which was published in Nature, this current drought is the driest in 1200 years.
What is a Mega-Drought
Before going any further, I should define what a mega drought is. According to Columbia University, a mega-drought is a prolonged drought, or period of dryness, lasting at least 2 decades. Since the current Western-Mega Drought in the West has recently passed 20 years, it is now officially a mega-drought, unfortunately, that does not mean it is over yet.
Droughts Still Have Wet Times
It is worth noting that mega droughts may have some years of wetness, but the overall environment is still affected by the dryness in the long term. 2005 and 2019 were wetter than the rest of the years, but are still part of the drought. Other studies have shown that year-to-year changes in dryness are normal during droughts. However, the overall trend is still lower than normal. The two driest summers in the last 300 years were 2002 and last summer (2021).
Tree Rings Determine Drought Severity
The scientists study tree rings to determine the severity of droughts throughout history. The group collected data from hundreds of trees in a large area. Both living and dead can be used for data collection. Trees form rings as they age. Moisture levels in the soil determine ring sizes, the high the moisture levels, the bigger the rings, and vice versa.
Direct correlation between tree ring widths and modern weather patterns has been observed in other studies. Rings width is the best indicator for historic weather conditions. Using this, the scientists found that the second worst drought was in the 1500’s. The data used from these trees could only go back 1200, so it is not clear when there was a drought more severe than the current one.
How Long Will The Western Mega-Drought Last?
Previous mega-droughts lasted about 30 years. The researchers indicate that the current Western mega-drought is likely to also last about the same amount of time. The drought just passed the 20-year mark, so it will be around for the next 5-10 years. According to the research, human caused climate change is also partly to blame for the severity of the current drought. In fact, about 19% of the severity has mankind to blame.
The research showed that temperature, not rainfall, plays the biggest role in causing droughts. High temperatures mean that the air is better able to pull the water from the soil. This means that even if it rains a lot, the water will not last in extreme weather conditions.
No Surprise Here, Climate Change Plays a Major Role in the Mega-Drought
The current drought is also partly responsible for the increased frequency of wild fires and water shortages in the past years. Federal water managers have declared water shortages in the Colorado River. Arizona has since implemented cuts to water supply to many farmers to help reduce the strain on the water supply. Aquifers are also at record low water levels.
Dryness, Even After the Drought
Scientists also suspect that even after this drought is over, the environment is likely to continue becoming drier. Maps by US Drought Monitor show the increasing dryness of the area over time. Climate change is causing areas all around the globe to have the same future.