CLIMATIC HUMIDITY EFFECTS ON CONTROLLED SUMMER AERATION IN THE HARD RED WINTER WHEAT BELT
Aeration is an inexpensive way to improve grain storage conditions, but it can be difficult to implement immediately 
after harvest in much of the hard red winter (HRW) wheat belt due to high ambient temperatures. High nighttime relative 
humidity worsens this problem because the heat of condensation released during adsorption reduces aeration cooling, but the 
magnitude of this humidity effect is not well documented. A procedure was developed to calculate effective temperature (Teff), 
which coupled dry-bulb temperature (Tdb), wet-bulb temperature (Twb), and grain moisture content to predict the actual final 
grain temperature after aeration. Hourly historical weather data were used to determine the available aeration hours below 
24°C from mid-July through early August in Kansas, Oklahoma, Texas, eastern New Mexico, and eastern Colorado, along with 
nearby portions of surrounding states. Grain cooling was highly influenced by humidity. Actual available aeration hours 
averaged approximately 78% less during the periods studied compared to calculations based on Tdb alone. Airflow rates higher 
than 0.1 m3/min/t were found necessary to achieve sufficient grain cooling for the summer in Texas, Oklahoma, and southeastern 
Kansas. This effect was more pronounced in 10% than 12% moisture content wheat, because Teff was always lower for grain 
at 12% moisture content.