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Jason Davison
Post-Doctoral Scientist
Post-Doctoral Scientist

Communities and Collections

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Bias EPA?

The EPA funds scientists to do research. Then the EPA uses those same scientists to write new regulations to restrict air pollution. This is a controversy?

Almost every environmental scientist has received some form of funding from the EPA. The only people that would be completely outside of the EPA funding would either be not from the US or not an environmental scientist/engineer.

Fox news is stirring up, just to stir it up:
"This clearly violates the law and makes a mockery of the notion of ‘independent’ scientific review,” Energy and Environment Legal Institute General Counsel Steve Milloy said.

The Energy and Environmental Legal Institute receives its funding from the Koch family and Exon. Truly unbiased....
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Great article on why Canada should get involved with Yemen aid.

+Jacqueline Lopour 
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Yemen Crisis

Interesting piece on the current crisis in Yemen by +Jacqueline Lopour and Centre for International Governance Innovation. I really enjoyed learning about the current humanitarian issues facing Yemen.
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Integrated Hydrosystem Modeling of the California Basin

The Western United States is facing one of the worst droughts on record. Climate change projections predict warmer temperatures, higher evapotranspiration rates, and no foreseeable increase in precipitation. California, in particular, has supplemented their decreased surface water supplies by mining deep groundwater. However, this supply of groundwater is limited, especially with reduced recharge. These combined factors place California’s water-demanding society at dire risk. 

In an effort to quantify California’s risks, we present a fully integrated water cycle model that captures the dynamics of the subsurface, land surface, and atmospheric domains over the entire California basin. Our water cycle model combines HydroGeoSphere (HGS), a 3-D control-volume finite element model that accommodates variably-saturated subsurface and surface water flow with evapotranspiration processes to the Weather Research and Forecasting (WRF) model, a 3-D finite difference nonhydrostatic mesoscale atmospheric simulator. The two-way coupling within our model, referred to as HGS-WRF, tightly integrates the water cycling processes by passing precipitation and potential evapotranspiration data from WRF to HGS, while exchanging actual evapotranspiration and soil saturation data from HGS to WRF. Furthermore, HGS-WRF implements a flexible coupling method that allows each model to use a unique mesh while maintaining mass conservation within and between domains. Our simulation replicated field measured evapotranspiration fluxes and showed a strong correlation between the soil saturation (depth to groundwater table) and latent heat fluxes. Altogether, the HGS-WRF California basin model is currently the most complete water resource simulation framework as it combines groundwater, surface water, the unsaturated zone, and the atmosphere into one coupled system.

The simulation below illustrates the coupled model running for a six day time period. The first plot, Log Depth, is the surface water elevations over the entire basin in log base 10 units (so a value of -2 is actually 1 cm). The next plot illustrates Precipitation shown as meters per second. The third plot Evapotranspiration is the amount of water coming out of the surface and subsurface as evaporation and from plants (transpiration). The last plot is the change in soil moisture from the initial condition, these values are negative values because the soil is drying with time. 

I am presenting this research at the American Geophysical Union Tuesday, 15 December 2015 in San Francisco. Hope to see you there!
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California Basin Model

California is pumping groundwater at an uncontrollable rate. Currently, the California basin receives approximately 8,000 cubic meters per second of water over the entire domain. However, the state relies on groundwater resources and takes about 1,300 cubic meters per second. This ratio (approximately 15%) results in a drastic decrease of the water table. 

The video shown below is a simulation of the California Basin using HydroGeoSphere. The model takes into account surface water, groundwater, evapotranspiration, precipitation, and groundwater pumping. On the right hand side, the plot shows the depth to the groundwater table. On the left side, the plot show the change in water table from pre-development levels. 

The key point to pull from this figure is that the southern arid region has less precipitation, which causes a stronger and faster decrease in groundwater levels. 

#Groundwater   #Drought   #California  
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Great piece on the benefits of the Iran deal.  
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Sacramento River Modeling

I'm modeling surface water flow in Northern California using the HydroGeoSphere (HGS) model. Our model couples groundwater and surface water into one domain, and allows us to investigate the interactions of the surface and subsurface. 

The video below shows the surface water flow in Northern California. The white-green scale plots the water depth, and the moving spheres are particle tracking. The red color on the spheres indicates the stream velocity. 

This plot demonstrates the several rivers that supply water to the Sacramento Basin.  

Note: This simulation is not calibrated.

#California   #californiadrought   #Science   #water  
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Climate Change

President Obama just released a new plan called the Clean Power Plan. The plans goal is: sets achievable standards to reduce carbon dioxide emissions by 32 percent from 2005 levels by 2030.

In his speech, Obama said he has committed the United States to leading the world on this challenge. 

Please watch the video below that he released today and check out the action plan on the White House website:
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Missing Science

Gizmodo came out with an article titled Researchers Discover Fracking Fluids in Pennsylvania Well Water based on a recent Proceedings of the National Academy of Sciences (PNAS) article. The Gizmodo piece goes into the details of how the researchers were able to link contaminated well water to fracking fluids by using 2D gas chromatography coupled to time-of-flight mass spectrometry (GCxGC-TOFMS). 

So whats wrong with the article?
The Gizmodo article gets a lot of the science right, and I'm happy about that. But they are missing the most important part: 

How did the contaminated water move from the deep subsurface and into the shallow drinking water aquifers?

Did the researchers actually find the movement of deep fracking fluid being able to reach the aquifer? This finding would drastically change fracking regulation, and could alter the use of natural gas. I was honestly shocked after reading Gizmodo because I strongly believe that fracking is just as safe as any other form of subsurface drilling (e.g. traditional oil drilling, deep subsurface waste storage, geothermal energy). 

To the Journal
Luckily, the author included the link to the PNAS article (it is behind a paywall, let me know if you need access to a copy). And it turns out the tone of the scientific paper is a lot different. Here are the concluding thoughts:

The data released here do not implicate upward flowing fluids along fractures from the target shale as the source of contaminants but rather implicate fluids flowing vertically along gas well boreholes and through intersecting shallow to intermediate flow paths via bedrock fractures. Flow along such pathways is likely when fluids are driven by high annular gas pressure or possibly by high pressures during HVHF injection. Such shallow- to intermediate-depth contaminant flow paths are not limited to HVHF but rather have been previously observed with conventional oil and gas wells. As shale gas development expands worldwide, problems such as those that occurred in northeastern PA will only be avoided by using conservative well construction practices, such as intermediate casing strings, proper cementation, and mitigating overpressured gas well annuli.

The contaminated fluids were most likely caused by poor well construction. Well construction is still one of the most important methods to reduce contamination of the local groundwater. The drilling company only cased (lined) their well for the first 300 meters and then cased the well at drilling depths at 2100-2300 meters. Their casing method caused the fluids to flow through the rock fractures that intersected the uncased well (300 meters depth and below) which intersected the local drinking water wells. 

Gizmodo piece:
PNAS Article:

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European Geophysical Union

Who is all going to EGU 2015?

I'm excited!
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