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Tower_team:
PI: Dennis Baldocchi baldocchi@berkeley.edu - University of California, Berkeley
AncContact: Daphne Szutu daphneszutu@berkeley.edu - UC Berkeley
AncContact: Joe Verfaillie jverfail@berkeley.edu - University of California, Berkeley
Lat, Long: 38.1087, -121.6531
Elevation(m): -7
Network Affiliations: AmeriFlux, Phenocam
Vegetation IGBP: CRO (Croplands: Lands covered with temporary crops followed by harvest and a bare soil period (e.g., single and multiple cropping systems). Note that perennial woody crops will be classified as the appropriate forest or shrub land cover type.)
Climate Koeppen: Csa (Mediterranean: mild with dry, hot summer)
Mean Annual Temp (°C): 15.6
Mean Annual Precip. (mm): 421
Flux Species Measured: CO2, CH4, H2O
Years Data Collected: 2009 - 2017
Years Data Available:

AmeriFlux BASE 2009 - 2017   Data Citation

Data Use Policy:AmeriFlux CC-BY-4.0 Policy1
Description:
The Twitchell Island site is a rice paddy that is owned by the state and managed by the California Department of Water Resources. While Bare Peat field ...
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URL: http://nature.berkeley.edu/biometlab/fielddescription.html
Research Topics:
The research approach of the University of California, Berkeley Biometeorology Laboratory involves the coordinated use of experimental measurements and ...
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Acknowledgment: California Department of Water Resources; USDA/AFRI
Site Tasks
  1. This site’s data can also be used under the more restrictive AmeriFlux Legacy Policy.
    The AmeriFlux Legacy Policy must be followed if this site’s data are combined with data from sites that require the AmeriFlux Legacy Policy.
Site Photo More Site Images
Image Credit: Joe Verfaillie, 10/31/2013
Copyright preference: As long as credit is given
Site Publication More Site Publications
Knox, S. H., J. H. Matthes, C. Sturtevant, P. Y. Oikawa, J. Verfaillie, and D. Baldocchi. 2016. Biophysical controls on interannual variability in ecosystem-scale CO2 and CH4 exchange in a California rice paddy., Journal of Geophysical Research-Biogeosciences, 121, 978-1001.

Use the information below for citation of this site. See the Data Policy page for more details.

DOI(s) for citing US-Twt data

Data Use Policy: AmeriFlux CC-BY-4.0 License

This site’s data can also be used under the more restrictive AmeriFlux Legacy Policy.
The AmeriFlux Legacy Policy must be followed if US-Twt data are combined with data from sites that require the AmeriFlux Legacy Policy.

  • AmeriFlux BASE: https://doi.org/10.17190/AMF/1246140
    Citation: Sara Knox, Jaclyn Hatala Matthes, Joseph Verfaillie, Dennis Baldocchi (2023), AmeriFlux BASE US-Twt Twitchell Island, Ver. 7-5, AmeriFlux AMP, (Dataset). https://doi.org/10.17190/AMF/1246140

To cite BADM when downloaded on their own, use the publications below for citing site characterization. When using BADM that are downloaded with AmeriFlux BASE and AmeriFlux FLUXNET products, use the DOI citation for the associated data product.

Publication(s) for citing site characterization

Acknowledgments

Resources

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Note: Results are the number of downloads to distinct data users. The Download Count column indicates the number of times the data user downloaded the data. The Version column refers to the version of the data product for the site that was downloaded by the data user.

Year Range

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Year Publication
2021 Chu, H., Luo, X., Ouyang, Z., Chan, W. S., Dengel, S., Biraud, S. C., Torn, M. S., Metzger, S., Kumar, J., Arain, M. A., Arkebauer, T. J., Baldocchi, D., Bernacchi, C., Billesbach, D., Black, T. A., Blanken, P. D., Bohrer, G., Bracho, R., Brown, S., Brunsell, N. A., Chen, J., Chen, X., Clark, K., Desai, A. R., Duman, T., Durden, D., Fares, S., Forbrich, I., Gamon, J. A., Gough, C. M., Griffis, T., Helbig, M., Hollinger, D., Humphreys, E., Ikawa, H., Iwata, H., Ju, Y., Knowles, J. F., Knox, S. H., Kobayashi, H., Kolb, T., Law, B., Lee, X., Litvak, M., Liu, H., Munger, J. W., Noormets, A., Novick, K., Oberbauer, S. F., Oechel, W., Oikawa, P., Papuga, S. A., Pendall, E., Prajapati, P., Prueger, J., Quinton, W. L., Richardson, A. D., Russell, E. S., Scott, R. L., Starr, G., Staebler, R., Stoy, P. C., Stuart-Haëntjens, E., Sonnentag, O., Sullivan, R. C., Suyker, A., Ueyama, M., Vargas, R., Wood, J. D., Zona, D. (2021) Representativeness Of Eddy-Covariance Flux Footprints For Areas Surrounding Ameriflux Sites, Agricultural And Forest Meteorology, 301-302, 108350. https://doi.org/10.1016/j.agrformet.2021.108350
2019 Kim, Y., Johnson, M. S., Knox, S. H., Black, T. A., Dalmagro, H. J., Kang, M., Kim, J., Baldocchi, D. (2019) Gap‐Filling Approaches For Eddy Covariance Methane Fluxes: A Comparison Of Three Machine Learning Algorithms And A Traditional Method With Principal Component Analysis, Global Change Biology, . https://doi.org/10.1111/gcb.14845
2019 Sullivan, R. C., Kotamarthi, V. R., Feng, Y. (2019) Recovering Evapotranspiration Trends From Biased CMIP5 Simulations And Sensitivity To Changing Climate Over North America, Journal Of Hydrometeorology, 20(8), 1619-1633. https://doi.org/10.1175/JHM-D-18-0259.1
2019 Sullivan, R. C., Cook, D. R., Ghate, V. P., Kotamarthi, V. R., Feng, Y. (2019) Improved Spatiotemporal Representativeness And Bias Reduction Of Satellite-Based Evapotranspiration Retrievals Via Use Of In Situ Meteorology And Constrained Canopy Surface Resistance, Journal Of Geophysical Research: Biogeosciences, 124(2), 342-352. https://doi.org/10.1029/2018JG004744
2019 Hemes, K. S., Chamberlain, S. D., Eichelmann, E., Anthony, T., Valach, A., Kasak, K., Szutu, D., Verfaillie, J., Silver, W. L., Baldocchi, D. D. (2019) Assessing The Carbon And Climate Benefit Of Restoring Degraded Agricultural Peat Soils To Managed Wetlands, Agricultural And Forest Meteorology, 268, 202-214. https://doi.org/10.1016/j.agrformet.2019.01.017
2018 Baldocchi, D., Penuelas, J. (2018) The Physics And Ecology Of Mining Carbon Dioxide From The Atmosphere By Ecosystems, Global Change Biology, . https://doi.org/10.1111/gcb.14559
2018 Chu, H., Baldocchi, D. D., Poindexter, C., Abraha, M., Desai, A. R., Bohrer, G., Arain, M. A., Griffis, T., Blanken, P. D., O'Halloran, T. L., Thomas, R. Q., Zhang, Q., Burns, S. P., Frank, J. M., Christian, D., Brown, S., Black, T. A., Gough, C. M., Law, B. E., Lee, X., Chen, J., Reed, D. E., Massman, W. J., Clark, K., Hatfield, J., Prueger, J., Bracho, R., Baker, J. M., Martin, T. A. (2018) Temporal Dynamics Of Aerodynamic Canopy Height Derived From Eddy Covariance Momentum Flux Data Across North American Flux Networks, Geophysical Research Letters, 45, 9275–9287. https://doi.org/10.1029/2018GL079306
2018 Eichelmann, E., Hemes, K. S., Knox, S. H., Oikawa, P. Y., Chamberlain, S. D., Sturtevant, C., Verfaillie, J., Baldocchi, D. D. (2018) The Effect Of Land Cover Type And Structure On Evapotranspiration From Agricultural And Wetland Sites In The Sacramento–San Joaquin River Delta, California, Agricultural And Forest Meteorology, 256-257, 179-195. https://doi.org/10.1016/j.agrformet.2018.03.007
2017 Chamberlain, S. D., Verfaillie, J., Eichelmann, E., Hemes, K. S., Baldocchi, D. D. (2017) Evaluation Of Density Corrections To Methane Fluxes Measured By Open-Path Eddy Covariance Over Contrasting Landscapes, Boundary-Layer Meteorology, . https://doi.org/10.1007/s10546-017-0275-9
2016 Baldocchi, D., S. Knox, I. Dronova, J. Verfaillie, P. Oikawa, C. Sturtevant, J. H. Matthes, and M. Detto. (2016) The impact of expanding flooded land area on the annual evaporation of rice. Agricultural and Forest Meteorology, Agricultural and Forest Meteorology, 223, 181-193. https://doi.org/http://dx.doi.org/10.1016/j.agrformet.2016.04.001
2016 Knox, S. H., J. H. Matthes, C. Sturtevant, P. Y. Oikawa, J. Verfaillie, and D. Baldocchi. (2016) Biophysical controls on interannual variability in ecosystem-scale CO2 and CH4 exchange in a California rice paddy., Journal of Geophysical Research-Biogeosciences, 121, 978-1001. https://doi.org/10.1002/2015JG003247
2012 Hatala, J. A., Detto, M., Sonnentag, O., Deverel, S. J., Verfaillie, J., Baldocchi, D. D. (2012) Greenhouse Gas (CO2, CH4, H2O) Fluxes From Drained And Flooded Agricultural Peatlands In The Sacramento-San Joaquin Delta, Agriculture, Ecosystems & Environment, 150, 1-18. https://doi.org/10.1016/j.agee.2012.01.009
2012 Hatala, J. A., Detto, M., Baldocchi, D. D. (2012) Gross Ecosystem Photosynthesis Causes A Diurnal Pattern In Methane Emission From Rice, Geophysical Research Letters, 39(6), n/a-n/a. https://doi.org/10.1029/2012gl051303
2014 Knox, S. H.,, Sturtevant, C., Matthes, J.H., Koteen, L., Verfaillie,J., Baldocchi. D. (2014) Agricultural peatland restoration: effects of land-use change on greenhouse gas (CO2 and CH4) fluxes in the Sacramento-San Joaquin Delta, Global Change Biology, 21, 750-765. https://doi.org/10.1111/gcb.12745

BADM for This Site

Access the Biological, Ancillary, Disturbance and Metadata (BADM) information and data for this site.

BADM contain information for many uses, such as characterizing a site’s vegetation and soil, describing disturbance history, and defining instrumentation for flux processing. They complement the flux/met data.

* Online updates are shown on the Overview tab real time. However, downloaded BADM files will not reflect those updates until they have been reviewed for QA/QC.

Wind Roses

Click an image below to enlarge it, or use the navigation panel.
  • Image scale: 799m x 799m
  • Data Collected:
  • Wind roses use variables ‘WS’ and ‘WD’.
    Download Data Download Wind Rose as Image File (PNG)

    Wind Speed (m/s)

  • Graph Type
  • Wind Speed Scale
  • Wind Direction Scale (%)
  • Show Satellite Image
  • Show Wind Rose
  • Annual Average
    About Ameriflux Wind Roses
    Wind Rose Explanation
    wind rose gives a succinct view of how wind speed and direction are typically distributed at a particular location. Presented in a circular format, a wind rose shows the frequency and intensity of winds blowing from particular directions. The length of each “spoke” around the circle indicates the amount of time (frequency) that the wind blows from a particular direction. Colors along the spokes indicate categories of wind speed (intensity). Each concentric circle represents a different frequency, emanating from zero at the center to increasing frequencies at the outer circles
    Utility
    This information can be useful to gain insight into regions surrounding a flux tower that contribute to the measured fluxes, and how those regions change in dependence of the time of day and season. The wind roses presented here are for four periods of the year, and in 16 cardinal directions. Graphics are available for all sites in the AmeriFlux network based on reported wind measurements at each site.
    Data from each site can be downloaded by clicking the ‘download’ button.
    Hover the cursor over a wind rose to obtain directions, speeds and intensities.
    Note that wind roses are not equivalent to flux footprints. Specifically, the term flux footprint describes an upwind area “seen” by the instruments measuring vertical turbulent fluxes, such that heat, water, gas and momentum transport generated in this area is registered by the instruments. Wind roses, on the other hand, identify only the direction and speed of wind.
    Where do these data come from?
    The wind roses are based on observed hourly data from the sites registered with the AmeriFlux Network.
    Parameters for AmeriFlux Wind Roses
    To use wind roses for a single AmeriFlux site, the following parameters may be most useful:
    • Wind Speed Scale: Per Site
    • Wind Direction Scale (%): Per Site
    To compare wind roses from more than one single AmeriFlux site, the following parameters may be most useful:
    • Wind Speed Scale: Non-Linear
    • Wind Direction Scale (%): AmeriFlux
    Mar - Jun; 6am - 6pm
    Mar - Jun; 6pm - 6am
    Jun - Sep; 6am - 6pm
    Jun - Sep; 6pm - 6am
    Sep - Dec; 6am - 6pm
    Sep - Dec; 6pm - 6am
    Dec - Mar; 6am - 6pm
    Dec - Mar; 6pm - 6am