Resource 2




Managing the Temperature and Other Conditions Inside the High Tunnel

 

Resource 2

Searchable Databases of Weather and Ventilation Status Effects on Conditions Inside Nine High Tunnels in Wooster, OH May 10, 2022 – November 8, 2024

Use our large historical record to help select a ventilation status for your high tunnel based on its primary orientation (N-S or E-W), and your target temperature and forecasted weather (sky cover, air temperature, and wind speed and direction). Select a ventilation status for your high tunnel(s) – e.g., to help maintain a target temperature — more confidently.

Our nine high tunnels are in Fields 5 and 15 of Horticulture Unit 1 of the OSU-Wooster campus. Field 5 contains three HTs (30 ft x 80 ft, single layer) oriented east-west and Field 15 contains six HTs (21 ft x 48 ft, single layer) oriented north-south. We have recorded the following in and near these HTs every five minutes since early May 10, 2022:
1. Air temperature and relative humidity outside the HTs,
2. Wind speed and direction,
3. Solar radiation (converted to sky cover),
4. Air temperature and relative humidity inside the HTs; and
5. The position of the doors and sidewalls of each HT. These positions comprise the HT’s ventilation status, the extent to which it is open/closed.

Additional data are collected or calculated using the directly measured values. Wind speed and direction data is collected from the Wooster airport.

The ventilation status of eight of the HTs has been changed many, many times since May 10, 2022. One HT has remained fully closed since that time. Ventilation statuses were chosen specifically to ensure that multiple individual statuses were in place simultaneously at all times (i.e., under the same weather conditions). We have identified 625 possible ventilation statuses based on the positions of individual endwalls and sidewalls for all HTs (regardless of orientation) and have tested a total of 620 of them at least once since May 10, 2022.

Two portions of the entire dataset are available below. Filter one or both of them to obtain information that helps identify door and sidewall positions that may be appropriate for your HT(s).

Each column in the worksheets below contains a “down arrow” in the lower-right corner of Row 2 next to the column name. To proceed, click on each arrow and select the value(s) in that column that best represents your situation (current or forecasted weather) and goal (target temperature inside the HT). The outcome of the filtering will display:
a) instances in which we recorded similar internal and external conditions and
b) the ventilation status(es) associated with each scenario.

Temperatures and relative humidity levels inside a HT track weather conditions outside it, especially when the HT’s door, sidewall, and/or vent positions do not change. Changing the HT’s ventilation status is the best way to maintain target conditions inside it. Still, please keep two points in mind when examining output you create by filtering a worksheet(s).

First, we recorded the combination of conditions you selected and show the ventilation statuses during which those conditions were recorded. However, placing your HT in a ventilation status listed in the output does not guarantee that the target temperature you selected will be achieved. Please use ventilation statuses we report as research- and experience-based guides, not prescriptions.

Second, more data are available for some conditions and ventilation statuses than others. We update the database often and look to expand the number of HTs and locations used to enhance it. Check back often. As configured now, the worksheets allow you to filter for up to 192,000 unique combinations of sky cover, wind speed and direction, outdoor temperature, and target temperature inside the HT. Currently, all combinations matching all your filtering criteria and for which at least 12 data points are available are included. Cases lacking at least 12 data points are excluded, indicating they were not observed or observed less than twelve times between May 10, 2022 and November 8, 2024. Therefore, isolated searches (filtering operations) may return no data.

Your web browser (Chrome, Edge, Firefox, Safari) may affect your access to or the appearance of the worksheets below. We recommend using Chrome at this time. Also, the worksheets occasionally do not load with the page. If that occurs, please click the “refresh” button on your browser’s address bar. For questions about access, please contact Matt Kleinhenz (330-263-3810; kleinhenz.1@osu.edu).

Resource 2 Video Demonstration

 

East-West High Tunnels                                      North-South High Tunnels

 

For High Tunnels with an East-West Spine
(Orientation)

 

For High Tunnels with a North-South Spine
(Orientation)