Blog #4

In our most recent trip back to the NASA Jet propulsion lab, we had the fantastic opportunity to get two lectures from scientists who work there. The first lecture was about a new satellite that NASA is planning to launch called the NASA-ISRO SAR which is a satellite that helps radar earth's surface to investigate on subjects like earthquakes and climate change.

During out second lecture we discussed subsidence in the central valley. This was very interesting because not many people know what is going on underneath California. After more than five years of drought in California, this 2017 water year has seen above average rain and snowpack, which makes people wonder “is the drought over?,” well during our lecture with Tom G Farr we discussed this important topic.

On April 7, 2017, Gov. Jerry Brown issued Executive Order B-40-17, which officially ended the drought state of emergency in all California counties except Fresno, Kings, Tulare, and Tuolumne. Scientifically, however, the answer to this question needs consideration of California's three primary sources of water: surface water, snowpack, and groundwater.

Farr began the lecture by talking about InSar, which is an interferometric synthetic aperture radar that grant scientists information on groundwater levels and measures surface deformation. Groundwater is becoming a more important part of water resources because of historic water low’s in California, but this isn't anything new to scientists.

This issue of subsidence began during the 1960s. Before I get ahead of myself, subsidence is a lowering or collapsing of the ground. This can be a major problem for infrastructures like roads, buildings and trains. Many people do not really speak about this issue because they are more preoccupied about the drought itself and blame the lack of rain, but majority of our problems come from agriculture in California’s Central Valley. As of recently there have been stricter water regulations for the general public but in all seriousness we are barely aiding the conservation of water, when in reality, we are only saving about a less than 20% percent of it.

Groundwater aquifers recover much more slowly than surface water and are limited, among other things, by how much and how fast water can recharge. Unlike surface water, which can recover during a few days of heavy precipitation, groundwater aquifer recovery often takes years or decades. Groundwater systems are also relied upon more heavily during times of drought. In many areas of the state, groundwater systems have been worn out for long periods of time, even between droughts, that they have not recovered from. Excessive long term groundwater overuse resulting in groundwater consumption can cause subsidence and permanent loss of groundwater storage as well as water quality degradation and seawater intrusion. These long term impacts on groundwater have not been recovered by the recent weather. As I said before the real problem is with the agricultural industry. The only way we can actually help save California is by sharing information about subsidence, but still even though using less water at home doesn’t do as much as we initially thought it would, it's still something.