Thermal Radiometry to Validate Ensemble Evapotranspiration (ET) on Sustainable Small Farms

Project Overview

Project Type: Graduate Student
Funds awarded in 2024: $29,999.00
Projected End Date: 12/31/2026
Grant Recipient: UCD
Region: Western
State: California
Graduate Student:
Principal Investigator:
Dr. Mallika Nocco
University of California, Davis
Principal Investigator:
Dr. Ruth Dahlquist-Willard
University of California Cooperative Extension
Dr. Kyle Knipper
United States Department of Agriculture
Dr. Troy Magney
University of California, Davis
Dr. Manpreet Singh
Kings County Cooperative Extension


  • Agronomic: peanuts, radish (oilseed, daikon, forage), other
  • Fruits: citrus, other
  • Vegetables: cabbages, eggplant, greens (leafy), greens (lettuces), leeks, onions, peppers, radishes (culinary), taro, other
  • Additional Plants: ginger, herbs, trees


  • Crop Production: application rate management, conservation tillage, continuous cropping, cover crops, crop improvement and selection, crop rotation, double cropping, drought tolerance, fallow, greenhouses, high tunnels or hoop houses, intercropping, irrigation, low tunnels, multiple cropping, no-till, row covers (for season extension), shade cloth, stubble mulching, water management, water storage
  • Education and Training: decision support system, demonstration, extension, farmer to farmer, focus group, mentoring, networking, on-farm/ranch research, participatory research, technical assistance
  • Farm Business Management: whole farm planning
  • Production Systems: agroecosystems, holistic management, organic agriculture
  • Sustainable Communities: community development, ethnic differences/cultural and demographic change, leadership development, local and regional food systems, partnerships, public participation, quality of life, social capital, social networks, sustainability measures

    Proposal abstract:

    California's agricultural scene is diverse, harvesting
    hundreds of crops despite a notoriously variable
    climate[1]. As groundwater transitions to a
    regulated resource according to SGMA
    legislation of 2018[2]
    , smaller operations are
    more likely to suffer under uniform application due to
    typically having less resources to
    adapt[3]. Small farms are associated with
    overall higher crop and non-crop biodiversity and higher
    yields [4], and these growers deserve consideration as SGMA
    is implemented through 2040. 

    Since 2018 regulations, noninvasive satellite-based platforms
    have emerged to effectively normalize crop water use for
    farms as small as one-quarter acre. While the platform
    OpenET has been integrated into irrigation management
    and compliance strategies, the ensemble of equations used to
    produce ET field maps assume homogeneous canopies of
    theoretically large areas. 

    In contrast, growers in this study operate diverse
    cropping systems on less than 30 acres, thus they are
    interested in ensemble performance under these constraints.
    We partnered with 7 small farms in the critically overdrafted
    Kings Watershed Basin to perform aerial and ground surveys at
    100-1000 times satellite’s spatial resolution in thermal
    bands and evaluate predictions of ET from their perspective.
    Doing this, our project aims to support regulations that keep
    small farms viable.

    The project invites grower collaboration and two-way
    education by staging twice annual extension events and
    developing Digital ET Product Packages for participating
    farms. Workflows and processing code will be published for
    stakeholder access, research findings will be published at
    academic conferences and in peer reviewed journal(s).

    Project objectives from proposal:

    Research Objectives

    1. Estimate the seasonal vapor flux of small farms using physical
    and energy balance methods

    2. Evaluate the performance of satellite based models

    3. Review relevant Groundwater Sustainability Plan in support of
    equitable groundwater management and preserving a natural

    Educational Objectives

    1. Dissemination of products, information, and ideas among
    growers and researchers

    2. Collaboration among growers, researchers and community

    3. Community building among those interested in and impacted by
    Sustainable Groundwater Management 

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.