AgriMet NetworkTWG 2012Jama Hamel

CALI FORNI A NEVADA

OREGON I DAHO

WASHI NGTONMONTANA

WY OMI NG

C A N A D A

AgriMet Network Expansion Since 1983

AgriMet Partnerships– Over 25 entities, including:

• Federal agencies• State agencies• Soil & water conservation districts• Universities• Public utilities• Private enterprise

AgriMet Operations:

Data Collection

Hourly Data Transmissions

– Channel 170 (100% HDR in 2008)– Transmit from 00:15:00 to 00:30:00– Stations transmit alphabetically– Data posted to the website each hour

AgriMet Operations:

ET Computation

AgriMet uses the 1982 Kimberly-Penman ET model

• Developed by USDA Agricultural Research Service in Kimberly, Idaho

• Alfalfa based reference model

)e-e(W6.43+

+G)-R(+

=ET asfnr

Crop coefficients relate reference ET to crop specific ET:

ETc = ETr x Kc

ETc Specific Crop Consumptive Use

ETr Reference Evapotranspiration (Alfalfa)

Kc Crop Coefficient (varies with time)

Generalized Crop Coefficients for Field and Row Crops

Time of Season, days

Kc

Kc mid Kc end

Kc ini

0.2

0.4

0.6

0.8

1.0

1.2

0.0

From: Allen, R. G

Daily Sum 7 Day 14 DayCrop Jul 7 Jul 8 Jul 9 Jul 10 Forecast ET Use Use

Alfalfa 0.25 0.27 0.25 0.25 0.25 18.8 1.7 3.4Apples 0.29 0.31 0.28 0.28 0.29 11.9 1.9 3.8Beets 0.29 0.31 0.29 0.29 0.30 10.1 2.0 3.7Potatoes 0.28 0.30 0.27 0.27 0.28 9.0 1.9 3.7Beans 0.28 0.30 0.28 0.28 0.28 8.1 1.9 3.8Field Corn 0.24 0.26 0.24 0.25 0.25 6.9 1.6 3.0Sweet Corn 0.24 0.25 0.24 0.24 0.25 6.4 1.6 2.9Winter Grain 0.14 0.14 0.12 0.11 0.12 20.2 0.9 2.2Spring Grain 0.28 0.30 0.25 0.24 0.25 19.6 1.9 3.9Onions 0.30 0.32 0.29 0.29 0.30 13.0 2.0 3.9Mint 0.28 0.30 0.28 0.28 0.28 14.9 1.9 3.8Lawns 0.24 0.26 0.25 0.24 0.25 17.8 1.3 2.5

Estimated Crop Water Use

Daily Crop Water Use (inches)

ET can vary considerably from one day to the next

AgriMet Operations:

Site Maintenance and Calibration

Precision Relative Humidity/Temperature Chamber

AgriMet Operations:

Data Quality Control / Quality Assurance

Automated Q/C

– Satellite transmission quality checks– Upper and lower limit checks on sensor data– Rate of change between consecutive

readings

Manual Q/C

– Every morning, data graphically reviewed– Geographically similar stations grouped– All weather parameters reviewed– Bad data estimated or deleted– Dependent computations (ET) recomputed

AgriMet Operations:

Other Uses of AgriMet Data

Other uses of AgriMet information– National Weather Service– State DEQ investigate pesticide application

and ground water contamination issues– Electric utilities model heating/air

conditioning and peaking power requirements

– State water departments

Other uses of AgriMet information:Verification and calibration of satellite technologies

Other uses of AgriMet information:Source of ET data for “Smart Irrigation Controllers” for Turf Grass

Questions?