NEON Airborne Takes Flight for 2018 Season

If you happen to be at a NEON field site during the peak of the growing season this year, look up. There’s a chance you’ll see one of the NEON Airborne Observation Platforms (AOPs) flying overhead.

At each terrestrial site a minimum of 100 km² will be surveyed over an area encompassing the NEON flux tower airsheds and distributed long-term observational sampling plots, representative vegetation types, and watershed boundaries for both terrestrial and aquatics sites. To minimize signal uncertainty due to plant phenology and to ensure spatial and temporal consistency in data products across multiple years, all terrestrial sites are scheduled to be flown during mean peak greenness, defined as the range of dates where MODIS NDVI is within 90% of the site maximum. To minimize atmospheric effects, data acquisition occurs at less than 10% cloud cover.

Where will we fly this year?

The 2018 flight campaign will run from March to October, covering 13 NEON domains and including 36 terrestrial sites and 14 aquatic sites using two payloads (Payloads 2 and 3 – see Tables 1-2 and Figures 1-2). The remote sensing instruments – consisting of an imaging spectrometer, a waveform light detection and ranging (LIDAR) instrument and a high-resolution digital camera – are installed into a DeHavilland DHC-6 Twin Otter aircraft flying at a nominal altitude of 1000 m above ground level (AGL) at a speed of 100 knots. The flight parameters enable meter-scale spectroscopy, decimeter-scale photography, and ~4 points-per-meter discreet and waveform lidar measurements at a sufficient signal-to-noise ratio to retrieve vegetation vertical structure and biogeochemical properties from measured reflectance spectra. This year’s data collection schedule will in an inaugural survey of the Guanica (GUAN) field site in Puerto Rico. The 2018 data collection season starts in March with the first flight over the San Joaquin Experimental Range (SJER) in California (D17: Pacific Southwest). The planes will follow peak greenness cycles across Alaska, the lower 48 states and Puerto Rico, with the final run taking place in Florida in September. Under the current plan, data will be collected from sites in the continental U.S. and Alaska three years out of every four, and in Puerto Rico and Hawaii every five years. 

If you are interested in tracking the 2018 season, daily flight reports can be found here. You can also sign up to receive daily email updates by NEON domain. Please note, you will only receive emails during the time period the AOP is in the domain you have signed up to follow. See below for the planned schedules of the two AOPs that will be flying this year.

Table 1: 2018 Flight Campaign Schedule – Payload 3

Table 2: 2018 Flight Campaign Schedule – Payload 2

Frequently Asked Questions

Can the AOP fly additional areas?

Due to the intensive nature of the NEON Flight Campaigns, we are unable to include additional flight areas to the existing NEON observatory collection plan. However, an additional payload is available to support Principal Investigator (PI)-led science flights via the NEON Assignable Assets program.

What remote sensing data are collected?

Measurements taken from the AOPs include a range of physical, biological and biochemical data available both as flightlines and mosaics, including:

• Topography (elevation, slope and aspect)
• Canopy chemistry (lignin, nitrogen, water content, xanthophyll cycle)
• Ecosystem structure (canopy height and Leaf Area Index (LAI)
• Total biomass maps and vegetation indices
• High-resolution orthorectified camera imagery

Why does the NEON project collect airborne remote sensing data?

The NEON airborne remote sensing system fills a critical hole in ecological data collection. Standardized, regular airborne data collection over the NEON field sites will allow scientists to monitor changes in vegetation patterns and canopy chemistry on a continental scale over an extended time period. These data will provide new insights into how invasive species are spreading over time and how changes in climate and land use impact forest health and their ability to sequester carbon.

Collection of AOP data is synchronized with data collected on the ground at each site. This allows scientists to develop a more comprehensive picture of how different observations scale and how measurements taken from airborne remote sensing instruments correlate with observations made on the ground.

NEON remote sensing data, along with tower sensors, soil sensors and observational field sampling, are freely available on the NEON data portal.

Are researchers using AOP data yet?

The data are already being used by scientists for many different projects. For example, a team led by Dr. Phil Townsend, an ecologist out of the University of Wisconsin, is using the data to build a spectral library of vegetation types that links physical and biochemical traits to spectral data. This will enable scientists to classify and map plant species using remote sensing data. At the Smithsonian Environmental Research Center (SERC), Dr. Jess Parker, a forest ecologist, plans to incorporate AOP data into his studies of tree growth and the exchange of carbon, radiation and moisture between forests and the atmosphere. In addition, there have been several educational projects using NEON data including a late-2017 project led by Ethan White.

The NEON remote sensing team is working closely with the science community to optimize data collection for the needs of researchers. Two NEON Technical Working Groups (TWGs) have been formed to guide further data collection efforts, one on airborne sampling design and one on LiDAR. These advisory groups, along with additional discussions with researchers using NEON remote sensing data, will help refine data collection protocols and guide future decisions for expanded data collection or new instrumentation.

Learn more about NEON airborne remote sensing.