COVID-19 Safety, Long term soil warming experiment, and the Lester B. Rowntree Memorial Weather Station

Things have been humming along at the field station this past year, although like everywhere else, it’s all a bit different. Through careful consideration with UC Berkeley, state, and local health officers, campus Environmental Health & Safety officers, and campus administration including the Vice Chancellor of Research, we have been able to carefully(!) host researchers and even some groups and classes at the field station while maintaining utmost safety protocols to prevent the spread of COVID-19. You can see our protocols here.

Part of the activity at the field station has included establishing a new long-term field experiment at the field station. Researchers from the Terrestrial Ecosystem Sciences group in the Earth and Environmental Sciences Division at Lawrence Berkeley Lab are conducting a soil warming experiment to measure changes in soil carbon and respiration in grassland habitat dominated by perennial grasses. Their project began in mixed conifer forest at Blodgett Experimental Forest. Before the plots go in the team is measuring site characteristics and soil properties by performing the following measurements.
– soil coring and soil analysis
– piezometers to measure water table depth
– root zone imaging
– electromagnetic induction (EMI) surveys to measure apparent subsurface electrical resistivity
– electrical resistivity tomography (ERT) to measure subsurface soil structure
– vegetation survey.

EMI Survey
Dr. Baptiste Dafflon performing the electromagnetic induction survey of the grassland site at Point Reyes Field Station. (Image: Allison Kidder)


Dr. Baptiste Dafflon and Dr. Yuxin Wu conduct the Electrical Resistivity Tomography (ERT) survey in the grassland site at Point Reyes Field Station. (Image: Allison Kidder)

We look forward to continued developments with this project!

In other news, our weather station has been dutifully collecting weather data since January 7, 2020. Thanks to the stellar work by UC Natural Reserve System Weather Station Technician, Wendy Baxter, and UCNRS IT technician, Kevin Browne, all sensors and solar systems have been recording with no problems. We are still working on uploading the weather station’s data stream, a process that’s been delayed by our exceptionally slow satellite internet service. 

In the meantime, we are pleased to announce our new weather station has been named the Lester B. Rowntree Memorial Weather Station. Les Rowntree (1938-2019), a well-known geographer and environmental scientist, provided the foundational gift that made the weather station possible. He supported the Point Reyes Field Station because of his long-standing interest in California’s unique climate and natural history. We had the following bronze plaque created that will be posted at the base of the weather station.

The bronze plaque memorializing Point Reyes Field Station’s weather station in honor of Lester B. Rowntree (1938-2019).

The data generated by our weather station is available by request. Please email Wendy Baxter with the dates you require.




New weather station on the way

Thanks to some generous donors and the UC Natural Reserve System, Point Reyes Field Station is installing a weather station! The weather station will be a part of UC Natural Reserve System’s network of weather stations and provide a record of weather-related information at the field station’s location in Olema Valley. During the past year we have worked closely with Point Reyes National Seashore to obtain necessary project permits and approvals (e.g., cultural and historic resources, National Environmental Quality Act, etc.). Now the most exciting part is happening: building the weather station.


The base of the weather station’s 30-foot aluminimum-frame tower will be attached to a metal frame anchored in a concrete base and held in place by three guy wires. Powered by an array of solar panels set up adjacent to the tower, all the environmental sensors and other equipment will be attached to the tower or deployed at ground level nearby. Sensors will include temperature, relative humidity, wind speed, total solar radiation, photosynthetically active radiation, precipitation, barometric pressure, and soil moisture and temperature to half meter depth. We are also installing a Phenocam, which will regularly photograph the vegetation in Olema Valley north of the tower, eventually providing a long-term record of seasonal changes and shifts in vegetation patterns over time. The data from the sensors will be sent via radio to a receiver at the Hagmaier House, then channeled to our satellite internet system, and eventually to the data storage location for the UC NRS weather stations.


Installation of the weather station is occurring in two phases: 1) building the concrete base and the solar array, and 2) installing the tower and the sensors. Of course, each phase includes many steps and lots of coordination!


A few weeks ago we built the concrete base and the solar array. Zac Tuthill, the Assistant Manager of Blue Oak Ranch Reserve, kindly took the lead for the build and Wendy Baxter, the UC Natural Reserve System’s Weather Station Technician, assisted. Before we drove the truck to the site, the Seashore’s roads and trails crew kindly mowed the area for us, giving us a clear place to work and reduce fire hazard. Here’s a view of the freshly mowed spot.

Mowed grassy area where weather station will be located


After determining the most level spot we started digging a hole for the 3 ft x 3 ft x 1 ft concrete base. The soil in the grassland was loamy and quite easy to dig. Zac then made quick work of building the frame for the concrete pour and really got into making sure it was level.

Making sure the wood form for the base is level


Zac then cut steel rebar to fit in a grid inside the concrete frame, adding needed strength to the base. Wendy and Zac then installed two 90 degree PVC pipe conduits for wires to run from the solar array and the rain gauge to the tower. You can see the tops of these conduits in the photo below on the left side of the wood frame, with tape covering the top of each of the pipes to prevent concrete from falling inside. Zac mixed bag after bag of concrete with water from a water tender he towed to the site, pouring each bag of mixed concrete into the frame while Wendy and I spread out the concrete and ensured even coverage.

Mixing the concrete


Wendy and Zac insert the metal frame into the concrete. The frame will eventually support the tower and was carefully aligned due north using a compass.  The wood boards were placed beneath the metal frame to ensure it did not set into the concrete. That way we can adjust the height of the frame and tower later if needed.

Inserting the steel base into the concrete for the 30-foot tower


Once the concrete had cured for about 45 minutes Zac and I signed the concrete to mark the occasion for posterity (“PRFS 2019”).Zac and Allison sign the concrete base



The next day’s tasks was to remove the wood frame around the concrete base and build the solar array that will power all the sensors, the Phenocam, and data transmitter. The solar array rests on a base of pressure-treated 4 in. x 4 in. wood on top of four buried concrete piers with metal straps to hold the wood. After deciding on a level spot near the tower — but not too near so things falling from the tower don’t hit the solar panels — we dug areas to place the concrete piers and leveled, leveled, leveled. Wendy and Zac fine-tuned the alignment of the tracks for the solar array using a compass to make sure it faces south. The array is built so all angles of the solar panel can be adjusted as needed.Aligning the solar array using a compass


Zac and Wendy mount the solar panels onto the tracks on the base. Zac and Wendy attach the solar array to its base


Here’s a view of the completed concrete base and solar array awaiting the tower and sensor gadgetry.  The locking white metal box will placed at the base of the tower and house the two batteries.

Completed solar array and concrete base for 30-foot tower


The 30 foot tower and sensors are on their way to UC Berkeley as I write this. Stay tuned for a report on the installation of the tower in the near future!