Feedback Mechanisms From Human Activities: Discoveries Using Data From The Oklahoma Mesonet Ken Crawford, Director Oklahoma Climatological Survey Regents’ Professor of Meteorology The University of Oklahoma September 28, 2004

Current Position Title: Program Director Integrated Surface Observation Systems Office of Science and Technology National Weather Service Headquarters Silver Spring, MD 20910

The Oklahoma Mesonet (Average Spacing is ~30 km)

Site Exposure: “The” Critical Issue In Acquiring Quality Data

The Impact of Trees – Blackwell Large trees are located SE of the Blackwell Mesonet site. How do they impact the observations?

The Impact of Trees – Blackwell Trees toward the SW and SE reduce the average (SW and SE) wind speed by more than 50% compared to the statewide average. Wind anomalies at nearby sites do not correspond with the anomalies at Blackwell. Wind anomalies at Blackwell (and the nearby sites) occur on a smaller scale than the distance between the sites.

Nighttime Temperature Anomalies at Blackwell

The average nighttime temperature at Blackwell with a SE wind is almost 10C below the statewide average. The SE wind anomaly at Blackwell does not occur at nearby sites.

Temperature (comparison between Micronet and nearby Mesonet sites) MATT HAUGLAND Pasture-Level Influences Note the cold anomaly mid-way between two Mesonet sites spaced 20 miles apart!

Several trees to the southeast of a site result in low measured values of radiation during the first several hours of the day. Blue line: an unobstructed station The Impact of the Near-Sensor Environment on the Resulting Observations

Related Research and Discoveries Now Possible The Impact of Soil Moisture and a Soil Moisture Climatology for Oklahoma

Impact of an Isolated Irrigated Field on Boundary Layer Temperatures 8 August 1998 — 23:00 UTC

Altus Site Photos

Statewide Time Series of Soil Moisture The annual cycle of Fractional Water Index values for Oklahoma with four soil moisture phases (I-IV) identified. (6 years of data)

Hollis, OK — 1998 Meteogram of Fractional Water Index Rain gauge was broken during the summer, but almost no rain fell during that time. Rain gauge was broken during the summer, but almost no rain fell during that time. 60 & 75 cm soil moisture did not recover by the year’s end, even with winter precipitation. 60 & 75 cm soil moisture did not recover by the year’s end, even with winter precipitation.

Time/Depth Scales Of Observed Precipitation Last 30 Days

Time/Depth Scales of Soil Moisture Fractional Water Index at 5 cm — Ending 10/12/03

Time/Depth Scales of Observed Precipitation Last 120 Days

Time/Depth Scales of Soil Moisture Fractional Water Index at 75 cm — Ending 10/12/03

Time/Depth Scales of Soil Moisture Fractional Water Index from Fairview, OK at 4 Depths (5 cm to 75 cm) for the 30 Day Period Ending 10/12/03

Related Research and Discoveries Now Possible… Linear Relationship Between Root Zone Soil Moisture and Surface Heat Fluxes

Linear Correlation of Fluxes With Respect To Soil Depth SH = Flux of Sensible HeatLH = Flux of Latent Heat

Related Research and Discoveries Now Possible… The Impact of Vegetation (Oklahoma Winter Wheat)

Mesonet Site Locations “Wheat” Sites “West” Sites “East” Sites

Dew Point Changes on 27 March 2000

27 March 2000 – Local Impacts Visual greenness for the week ending 6 April 2000 Wind direction (WDIR) & dew point (TDEW) from Freedom, OK

SOM Seminar – Matt Haugland Across Oklahoma’s Winter Wheat Belt The Diurnal Cycle of Land-Atmosphere Interactions Reverse Inland “Sea breeze” Circulation COOL WARM HHL HLL Divergence The city-center (i.e., the wheat belt) becomes warm during the afternoon and induces low-level convergence.

SOM Seminar – Matt Haugland Across Oklahoma’s Winter Wheat Belt The Diurnal Cycle of Land-Atmosphere Interactions After Harvest, June (WWB – AC) Diurnal Temperature & Pressure Anomalies The result is an afternoon warm anomaly over the wheat belt and a co-located low pressure anomaly.

Related Research and Discoveries Now Possible… The Memory of Mother Earth

Rainfall Footprint from 5-7 August 1994

Blackwell & Pawnee: Week 1

Blackwell & Pawnee: Week 2

Five Days Later: 12 August 1994 Double-lobed pattern in the air temperature field was evident in the afternoon analysis 5 days later.

Five Days Later: 12 August 1994 Double-lobed pattern in the dew point field was evident in the afternoon analysis 5 days later.

Other Agricultural Dividends “The Mesonet has proven to be one of the most valuable production and marketing tools available to Oklahoma producers.” “The Mesonet has proven to be one of the most valuable production and marketing tools available to Oklahoma producers.” Mark Hodges, Oklahoma Wheat Commission “Mesonet data was critical to provide documentation of the current drought.” “Mesonet data was critical to provide documentation of the current drought.” Gerald Downing, Latimer County Emer. Mgmt.

The End

Oklahoma Mesonet: Overview ~3300 sensors and ~250 computers linked ~3300 sensors and ~250 computers linked About a million observations a day About a million observations a day –~98.5% of observations available in real-time 2-way communications (very important component) 2-way communications (very important component) Sites are solar powered Sites are solar powered –Runs on the energy of a nightlight 30-day storage in the on-site data-loggers 30-day storage in the on-site data-loggers First data from 1 January 1994 First data from 1 January 1994 ~3 Billion observations in the archives ~3 Billion observations in the archives Produce ~63,000 products and files for users each day Produce ~63,000 products and files for users each day

Oklahoma Mesonet: Overview Conceived as an idea following the disastrous Tulsa flood of May 1984 Conceived as an idea following the disastrous Tulsa flood of May 1984 Similar ideas for an agricultural network were blossoming in Stillwater, OK Similar ideas for an agricultural network were blossoming in Stillwater, OK Initial funds: $2.7M in January 1991 Initial funds: $2.7M in January 1991 Network became operational on 1 January 1994 Network became operational on 1 January 1994

Measurements at a Mesonet Site [Most observations every 5 minutes] Air Temperature — 1.5 m and 9 m Air Temperature — 1.5 m and 9 m Barometric Pressure Barometric Pressure Rainfall (tipping bucket) Rainfall (tipping bucket) Relative Humidity — 1.5 m Relative Humidity — 1.5 m Solar Radiation — 1.8 m Solar Radiation — 1.8 m Soil Temperature — Bare/Natural Sod to 30 cm Soil Temperature — Bare/Natural Sod to 30 cm Wind Speed/Direction — 10 m [+ speed at 2 m] Wind Speed/Direction — 10 m [+ speed at 2 m] Soil moisture — 4 depths to 75 cm; ~100 sites Soil moisture — 4 depths to 75 cm; ~100 sites

Mesonet Tower and the Suite of Instruments

Communications: RF Links (2-way communications ensures ~98.5% data availability in real-time and ~99.7% archival availability)

Integrated QA System

A large transmission pole to the southeast of a site causes an obstruction to the pyranometer for about an hour each morning. The Impact of the Near-Sensor Environment on the Resulting Observations

Time Series Plot of ALTU and TIPT 7 August – 8 August 1998

Daily-Maximum Heat Flux Versus Soil Water cm Sample Layer - Linear - R 2 = (SH) - R 2 = (LH) 60 cm 229-L Sensor - Linear - R 2 = (SH) - R 2 = (LH)