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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  • Relative Greenness (RG) portrays how green the vegetation is compared to how green it has been over the historical reference period (1989-last year).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.

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NWCG Latest Announcements

New Job Aids Available: Packing Lists for Wildland Fire Fireline Personnel and Support Staff, J-101 and J-102

Date: December 3, 2024
Contact: NWCG TRAINING

Two new job aids are now available: Packing List for Wildland Fire Fireline Personnel, J-101 and Packing List for Wildland Fire Support Personnel, J-102, should serve as a baseline for items needed on a wildland fire assignment. These lists will help personnel prepare for a 14 to 21-day assignment on the fireline or in a support role.

References:

Job Aid Catalog

NWCG Packing List for Wildland Fire Fireline Personnel, J-101

NWCG Packing List for Wildland Fire Support Staff, J-102

NWCG Equipment Technology Committee Releases Safety Warning: 24-001 Stihl Chainsaw Toolless Fuel Cap Spill Prevention

Date: November 14, 2024
Contact: Equipment Technology Committee

The Equipment Technology Committee (ETC) has released Safety Warning: 24-001 Stihl Chainsaw Toolless Fuel Cap Spill Prevention. Misaligned toolless fuel caps on Stihl chainsaws have led to recurring fuel spillage, fuel ignition, and burn injuries during wildland fire management operations.

This Safety Warning is intended to highlight the details and recommended procedures for the installation of a Stihl chainsaw toolless fuel cap, as well as how to identify and correct a misaligned, damaged, or broken fuel cap to help prevent fuel spillage.

References:

NWCG Safety Warning: 24-001 Stihl Chainsaw Toolless Fuel Cap Spill Prevention

Advertencia de equipos 24-001: Prevención de derrames de la tapa de combustible sin herramientas de la motosierra Stihl

NWCG Alerts

The Incident Position Standards and Next Generation Position Task Book are now available for Equipment Time Recorder (EQTR)

Date: November 13, 2024
Contact: Incident Business Committee

NWCG is excited to announce that the NWCG Incident Position Standards for Equipment Time Recorder, PMS 350-51 and NWCG Position Task Book for Equipment Time Recorder (EQTR), PMS 311-51 are now available.

The Performance Support Package, which for EQTR, includes the Incident Position Standards and Next Generation Position Task Book were developed through the Incident Performance and Training Modernization (IPTM) effort. The Performance Support Package will support trainees, those qualified in the position, and evaluators.

References:

NWCG Equipment Time Recorder Position Page

NWCG Incident Position Standards for Equipment Time Recorder, PMS 350-51

NWCG Position Task Book for Equipment Time Recorder (EQTR), PMS 311-51

The Incident Position Standards and Next Generation Position Task Book are now available for Personnel Time Recorder (PTRC)

Date: November 13, 2024
Contact: Incident Business Committee

NWCG is excited to announce that the NWCG Incident Position Standards for Personnel Time Recorder, PMS 350-53 and NWCG Position Task Book for Personnel Time Recorder (PTRC), PMS 311-53 are now available.

The Performance Support Package, which for PTRC, includes the Incident Position Standards and Next Generation Position Task Book were developed through the Incident Performance and Training Modernization (IPTM) effort. The Performance Support Package will support trainees, those qualified in the position, and evaluators.

References:

NWCG Personnel Time Recorder Position Page

NWCG Incident Position Standards for Personnel Time Recorder, PMS 350-53

NWCG Position Task Book for Personnel Time Recorder (PTRC), PMS 311-53