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Fuel Moisture: Vegetative Greenness

Wildland Fire Assessment System (WFAS) AVARR NDVI Greenness Reference is the comprehensive source of images, data archives, and methods for handling.

These images, derived from a satellite sensor, have been produced weekly since 1989, producing a historical record of vegetation phenology that can be used to characterize current vegetation greenness. They can be used to cross-reference with drought assessments and other characterizations of plant development, moisture stress, and curing. Cloud cover can have a significant impact on image quality in portions of the image.

While not an estimate of live fuel moisture, spatial distribution of NDVI estimates and its climatological derivatives can provide important insight to past and current vegetative state and overall landscape flammability during the growing season.

There are several depictions that allow you to evaluate the current NDVI status:

  • Normalized Difference Vegetation Index (ND) is the current derived value from which all the other climatological depictions are derived.
  • Departure from Average Greenness (DA) portrays the absolute difference between current value and the historic average greenness for the corresponding week of the year based on all years 1989-last year.
  • Relative Greenness (RG) portrays how green the vegetation is compared to how green it has been over the historical reference period (1989-last year). Because each pixel is normalized to its own historical range, all areas (dry to wet) can appear fully green at some time during the growing season.
  • Visual Greenness (VG) portrays vegetation greenness compared to a very green reference such as an alfalfa field or a golf course. The resulting image is like what you would expect to see from the air. Normally dry areas will never show as green as normally wetter areas.

This image of Departure from Average Greenness is for September 12, 2011

Image
Departure from Average Vegetative Greenness. Example graphic from the Wildland Fire Assessment System for September 12th of 2011.

NWCG Latest Announcements

The Next Generation Position Task Book and Incident Position Standards are now available for Safety Officer, Field (SOFF)

Date: July 26, 2024
Contact: Risk Management Committee 

NWCG is excited to announce that the NWCG Incident Position Standards for Safety Officer, Field, PMS 350-81 and NWCG Position Task Book for Safety Officer, Field (SOFF), PMS 311-81 are now available.

The Safety Officer, Field (SOFF) is responsible for monitoring operations on an incident from a risk management perspective to provide for the welfare of incident resources and the public. The new Incident Position Standards and Next Generation Position Task Book are developed through the Incident Performance and Training Modernization (IPTM) effort.

References:

NWCG Safety Officer, Field (SOFF) Position

NWCG Incident Position Standards for Safety Officer, Field, PMS 350-81

NWCG Position Task Book for Safety Officer, Field (SOFF), PMS 311-81

Updated NWCG Standards for Electronic Documentation (eDoc), PMS 277

Date: July 25, 2024
Contact: Incident Planning Subcommittee 

The Incident Planning Subcommittee has updated the NWCG Standards for Electronic Documentation (eDoc), PMS 277.

The NWCG Standards for Electronic Documentation (eDoc) establishes the standards for collection and retention of records on wildland fires. This July 2024 update will provide incident management teams the most current standards required to maintain incident records and submit them to host units at the close of an incident.

References:

NWCG Standards for Electronic Documentation (eDoc), PMS 277

eDoc Box Directory (zip file)

NWCG Off-Highway Vehicle Typing Standard Request for Comment

Date: July 24, 2024
Contact: Mobile Fire Equipment Subcommittee 

The Mobile Fire Equipment Subcommittee has released Equipment Bulletin 24-002 NWCG Off-Highway Vehicle (OHV) Typing Standard - Request for Comment. This bulletin outlines the proposed NWCG OHV typing standard, as well as the business need for establishing the standard. Comments on the proposed standard will be accepted through August 15th using the comment form linked below.

References:

ETC-EB-2024-02: NWCG Off-Highway Vehicle (OHV) Typing Standard - Request for Comment

NWCG Off-Highway Vehicle (OHV) Typing Standard Comment Form

NWCG Standards for Airtanker Operations, PMS 514 - DRAFT

Date: July 18, 2024
Contact: National Interagency Aviation Committee 

A draft version of the new NWCG Standards for Airtanker Operations, PMS 514, is now available. The NWCG Standards for Airtanker Operations establishes the standards for dispatching, utilizing, and coordinating airtankers on wildland fires. As this is the first edition of these standards, the National Interagency Aviation Committee (NIAC) requests review and input into the 2025 final publication.

Please review and provide feedback by September 1st, 2024 for consideration. Feedback can be provided utilizing the NWCG Publication Review Form.

References:

NWCG Standards for Airtanker Operations, PMS 514 - DRAFT

NWCG Publications Review Form