The Sacramento Branch is pleased to present:
Bruce Daniels, Ph.D.
Hydroclimatology, University of California Santa Cruz
President, Board of Directors, Soquel Creek Water District
Past Member and Chair, Regional Water Quality Control Board, Central Coast
"California Climate, Groundwater,
and Their Interrelated Future"
If the primary input to groundwater models, which is recharge, is not accurate, then there is little hope that those models will produce correct results. In other words, Garbage In – Garbage Out.
It would indeed be a shame for a SGMA Agency to go through all the effort of generating a plan and then spending twenty years implementing it, only to discover that the undesirable results have not been resolved. If climate change effects are not properly and fully incorporated, then this outcome could be likely.
This talk will present some of the subtleties of climate system science and its relationship to recharge. This climate system and recharge relationship is very complex and probably too little known or fully appreciated.
For example, recharge is non-linear with respect to total annual precipitation with the largest storms producing the most recharge. We’ve found when precipitation gets reduced by about 30-35%, then we get essentially zero recharge!
Precipitation event timing patterns we have observed to be changing. Over the next 30 years, such timing change has been shown to reduce the recharge by about 7% less, even with no changes at all in total annual precipitation.
Changes of temperature alone can cause substantial impacts on groundwater recharge. Every degree Fahrenheit of temperature increase causes a 4% increase of evaporation potential. Since the ET fraction of total precipitation is already often quite high at 50%–70%, then even a moderate increase in that evaporation would represent a huge water loss. This is demonstrated by applying the predicted 7°F temperature increase to a California groundwater basin to show those substantial impacts on groundwater recharge.
The predictions of California sea level rise are as much as 4½ feet. Coastal basins can only be protected from the additional seawater intrusion induced by this sea level rise by a corresponding rise of inland water levels just to keep the gradient constant. Such a protective action can be translated into a virtual loss of recharge, e.g. for a small coastal basin an effective loss of 500af each year for the next 85 years.
About the Speaker:
Bruce Daniels has a Ph.D. in Hydroclimatology (science of climate change and its impacts on water resources) from UC Santa Cruz. His advisers were Professor Lisa Sloan (climatology) and Professor Andy Fisher (hydrology). Bruce also has a M.S. and B.S. in Computer Science from M.I.T. Bruce has served on the Board of Directors of Soquel Creek Water District (Santa Cruz County) for 16 years. Bruce was previously appointed by the Governor and served two terms as a Member and was elected Chair of the Central Coast Regional Water Quality Control Board. Bruce had a +30-year career in the computer industry. His most significant accomplishments were at Apple where he worked on the original Macintosh Computer development team and was the software manager for its conceptual predecessor, the Lisa Computer. Other firms were Hewlett-Packard, Borland, Oracle, Sun Microsystems, and his start-up Singular Software.
Rodney Fricke will speak briefly on the status of the Sacramento Branch finances, attendance, and membership.
ANNOUNCING SCHOLASTIC SPONSORSHIP OPPORTUNITIES
All Proceeds to Benefit Science Students
GRA Sacramento Branch has a history of supporting university-level science students. Our Scholastic Sponsorship Program is an opportunity to publicize your business while contributing toward a good cause. The cost is minimal; if interested, please contact Judie Smith at 707-374-4300 or 209-712-9020 or firstname.lastname@example.org.
THIS MONTH'S SPONSOR:
Geocon is a California based multi-disciplined engineering firm specializing in environmental engineering and contracting, geotechnical engineering, engineering geology, materials testing, and special inspection services for State agencies, municipalities, and private entities. With over 200 professionals and support staff housed in nine strategically located offices throughout California, Geocon can easily meet the needs of our clients.
COST & RSVP:
Costs and menu are shown below. GRA is unable to assure food and room for you without an RSVP. Using GRA's automated RSVP process is quick and painless!
Usual great food, including two meat entrées, salad, rice, potatoes, vegetable and Iced Tea. A No-host beer and wine bar will be available.
If you RSVP by Noon on Monday, July 11th, 2016 the meeting costs are:
*Retired professionals receive a 10% (rounded to the nearest dollar) discount on any meal.
If you RSVP after Noon on Monday, July 11th, 2016, or walk-in, a $3.00 surcharge will be added to the meeting costs. Cancellations must be made by Noon on Monday, July 11th, 2016