Arable Web 9.0.0

Release Date: February 23, 2021

Instance affected: Production

Hostnames: arable.arable.com

Browsers: IE 11, Chrome 86, Firefox 82, Edge 86, Safari 13.1/12.1, iPad 12/13

Type of Release: Major

Version: 9.0.0

Release Overview

Arable Web 9.0.0 is a major release introducing three new water-related insights features, now in beta release with a select group of customers. To familiarize our customers with the new features before they are widely released, we'll run through them here. If you want to be part of the beta trial to explore these features before they are in full release, contact your account representative. The three features are: 

• Water Balance, or the amount of water retained by the crop. It’s calculated as precipitation plus irrigation, minus canopy evapotranspiration (ET_c). While precipitation and ET_c are measured by the Arable Mark directly, the irrigation runtime is measured through the Arable Bridge using a GEMS Pressure Switch. This setup is tailored for drip irrigation systems. Future releases will extend support to central pivot irrigation systems as well. The water balance measurement in this release is relative (i.e., starts at zero at the beginning of the season). Total balance and weekly change are also tracked and shown. The next 7-day forecast assumes zero irrigation, providing a recommendation for what to enter in the next irrigation cycle.
• Soil Moisture status as a percentage of available water (field capacity minus permanence wilting point). A Sentek Drill & Drop soil moisture probe is used for the measurement (connected to Arable Bridge). The soil moisture readings provide a complementary check to the ET_c-based water balance for understanding the water retained in the soil. A refill threshold can be defined to help trigger additional irrigation vs. normal schedule.
• A Heat Stress Hour count from season start, and per week. Heat stress hours are counted as the number of sunshine hours (SWdw > 10 W/m²) with Tbelow above the photosynthesis temperature threshold. The temperature threshold is taken from the GDD max temp for the crop (if there is one) or defaults to 36°C. The existence of heat stress can be used to trigger additional irrigation in order to cool down plants and restart the photosynthesis process.

Associated with the water insights beta features, we are introducing a new key building block called Sites. A site is a physical management unit with similar treatment, e.g., an irrigation block or field. It can contain one or more Arable Mark devices. Sites can hold multi-year data streams that span multiple deployments. As we later expand from beta to general availability of Sites,  other parts of the UI will be transitioned from current deployment locations to sites.

We hope you will enjoy this new release and feedback is always welcome through Customer Success (support@arable.com) or via your account manager.

New Features

• Name the site
• Draw boundaries for the site on a map (can be edited later)
• Select which Mark locations are relevant to use for the site (the software will by default include all the ones located within the boundaries you draw)
• Set the field capacity and permanent wilting point for the soil at the site (the info modal will be very helpful here. You can add/edit later when graphing your results)

• Water balance
• Water balance change
• Precipitation
• Irrigation
• ETc
• Soil moisture
• Soil moisture change
• Proximity to refill threshold
• Heat stress hours
• Total heat stress hours

For detailed descriptions of each of these measurements, see the info modals in each section, retrievable by clicking on the headings with dotted underlines.

During the beta period, only users with specific permission settings will be able to access the water insights feature. If you would like a demo or to get on the list for early access, please contact your Arable account manager.

We are introducing a unique machine learning (ML) model to derive an Arable field evapotranspiration (ETf), which is akin to reference ET (ETo). Arable’s ETf achieves greater accuracy than the FAO Penman-Monteith equation, and the latter is now only used as a fallback in rare conditions where the ML model is not yet trained. The crop coefficient (Kc) is calculated as before by using the NDVI reflectances over the canopy throughout the growing season. As part of the work to update the ET implementation using the new ML model, all the info modals related to ET have been updated.

A number of info modals have been updated in the system; notably the Seasons page (both location seasons and site seasons) shows new crop, varietal and growth stage modals. Locations are now in alphabetical order in the drop-down. If you decide to change the crop type, any existing growth stages will be replaced with the default setting.

Two new countries, Chile and Colombia, have been added to the Alerts (Mark 2) page voice and SMS channel options. Colombia is supported for voice calling alerts in addition to the normal mobile push notification, while Chile is supported with SMS as a second option. For more details, see the voice info modal at the top of the Alerts (Mark 2) page.

Defect Fixes

The account page has now a link to the https://developer.arable.com/ page in the info modal for “API Key.” This link will help you get started on using the Arable API.

The Activity log page had a deprecated link to the Account page for changing the subscriptions for a received alert. This link is now updated to point to the Alerts (Mark 2) page.

For GDD data to be shown on the Map page, a user should define a season, and the season should be currently active. To clarify this, the naming of Growing Degree Days in the Map drop-down has been changed to Growing Degree Days (Current Season).

Known Issues

While the Locations drop-down in the Export and Graph-Time page shows the start date of an historical location (inactive/dormant) in parentheses, the end date is not shown. This will be fixed in the next release.

The loading time for the Graph-Rank tab can be prolonged in certain circumstances (e.g., slow internet connection). It is planned to improve the performance in an upcoming release.

We have seen occasional issues with confirming the selection of the location to be included when creating a new season. This is under review for an upcoming hot fix. In the meantime, the issue gets resolved by refreshing the browser page.

Wind data as shown on the Arable Web Map page is the average for today. This is planned to be changed in a future release to current wind in order to be more actionable.

The Web UI for the Map and Settings pages does not explain to the user whether GPS is missing for a Mark (e.g., that it is temporarily deployed indoors). An info modal is planned for a future release to tell the user to move the Mark into GPS coverage (i.e., outdoors) and potentially to allow manual entry of the GPS coordinates for prolonged deployment inside.

To enable confirmation of successful soil moisture probe installation in real time, we plan to add Bridge status as part of the deployment message from the Mark to the backend, and have it populate in the API and UI (on the Devices page). As of now, the update will come with the first complete sync.

Sorting by last sync on the Devices page may show pending device locations at the top, regardless of sort order. This will be fixed in an upcoming release.

Frost and heat alerts are currently triggered based on the max/min 5-minute value of the hour. A hysteresis of 2°C above the threshold has to be achieved before another alert would be triggered again. This means that one 5-min anomaly value could lead to a re-triggering of the alert. An improved algorithm for the min/max temp that uses, e.g., the average of the top five 5-min values, is being assessed for an upcoming release.

Currently the NDVI graph does not show any indication that a drop can be due to cloudy days. To circumvent any misunderstandings, users can also review the solar radiation with the two-measurement graph feature.