NWT RESEARCH DATABASE

Regions: Inuvialuit Settlement Region, Gwich'in Settlement Area, Sahtu Settlement Area, Dehcho Region, North Slave Region, South Slave Region, Qikiqtaaluk Region

Tags: physical sciences, air quality, remote sensing, aerial photography, dust monitoring, spectrometry

Objective(s): To link studies conducted on the ground with data collected via satellite remote sensing, enabling a deeper understanding of the vulnerability and resilience of these ecosystems.

Project Description: This licence has been issued for the scientific research application No.4499. This airborne field campaign will link studies conducted on the ground with data collected through satellite remote sensing, enabling a deeper understanding of the vulnerability and resilience of these ecosystems, and how people within and beyond this region are responding to change. The ABoVE airborne campaigns can provide remote sensing data with higher spatial and temporal resolution than available from satellite sensors, as well as measurements that are not currently available from space. The ABoVE airborne campaigns offer unique opportunities to validate satellite data for northern high latitude ecosystems, develop and advance fundamental remote sensing science, and explore and exploit new scientific insights from innovative sensor combinations. For this permit application, we are adding some fieldwork components to validate airborne results. These include collecting water quality samples across a suite of lakes within the AVIRIS-NG flight lines, as well as collecting foliar (leaf) samples for spectral and chemical analyses. For 2019, the NASA Gulfstream-III aircraft with an L-band radar instrument, Dynamic Aviation King Air B-200 aircraft with a hyperspectral (AVIRIS-NG) instrument, and the Gulfstream-V with a laser altimeter (LVIS) will re-fly lines in the ABoVE study area. The flight teams will be based out of Yellowknife and Fairbanks airfields, but will be refueling at many different airports in the region. Overall flight coordination will be completed as required through official channels with the U.S. FAA and Transport Canada. The instruments have been cleared by NASA internal safety reviews, and the U.S. FCC has given authority to operate, and similarly in Canada, the Ministry of Industry has approved their operating parameters for the radar system. The instruments will not leave behind any footprint of its use. All sensor systems are fully integrated into the aircrafts and no sensors will be deployed outside the aircraft. These remote sensing instruments have been used around the world on various other NASA projects with no environmental impacts ever reported. The research team will identify locations to measure the fluxes of carbon dioxide and methane across an inundation gradient in lake systems within access from the Daring Lake field station. Lakes will be chosen based on previous sampling data (where available). Water samples will be collected to look at the relationship between water quality and recent precipitation and/or prior snow conditions. Fieldwork will include: 1) Float plane access to about ten -twelve lakes along the course from Yellowknife to Daring Lake. All samples can be collected from the center of the lake off the floatplane pontoons. Water quality samples will include the measurements of total nutrients, water isotopes, dissolved concentrations of organic and inorganic carbon, carbon dioxide and methane, as well as FTICR-MS characterization of organic carbon across lakes; 2) On site field deployment of a YSI EXO2 multi-parameter sonde will measure temperature, conductivity, dissolved oxygen, blue-green algae and CHLa, fDOM, and turbidity; 3) Additional samples will be collected for optical characterizations using a Seabird portable spectrometer (AC-S) designed to measure the in-situ absorption and beam attenuation of light in aquatic systems. This will be paired with measurements of surface reflectance measured from an ASD spectrometer; 4) Water samples will be transported from the synoptic sampling campaigns and brought to the Daring Lake field station where additional filtration and processing will be done. Samples will be placed on ice for shipment back to Yellowknife as soon as feasible; 5) At Daring Lake, sites will be identified suitable to measure open water – littoral, and upland fluxes of carbon dioxide and methane. Ideally, three different lake locations will be accessible to return to for an additional field season in 2020 and potentially 2021. Preliminary sampling will occur at the identified sites in and around Daring Lake for basic lake water and pore water chemistry, and dissolved gas concentrations. In total, no more than 7 liters of sample water will be transported back to Yellowknife as part of this summer field campaign. These samples will be returned to the University of Washington for further analysis. The research team identify a field plot as a relatively homogenous area of vegetation (no clear breaks in cover or species composition), with over fifty percent green cover preferred in a ten by ten meter sampling location. The team record the location using a precision GPS at the center of the plot for linkage to imagery. In forests, the team will tally the diameters of canopy trees within that area and estimate cover by species. In low vegetation types, the researchers visually estimate cover by species, and collect a photograph of the plot from above using a digital camera attached to a telescoping pole (thirty-foot maximum extension). Foliar samples are also collected. In most vegetation types, the collection of three foliar samples per dominant species (over twenty-five percent) cover and one to two samples per species with five to twenty-five percent cover. In forests and shrub lands, samples are collected from the sunlit portion of the crown. The exception to all of this is in grasslands, where the team will collect three clip samples representative of the vegetation. In all cases, a sample consists of twenty grams of fresh green foliar material. Following collection of these samples, the sample material is split three ways: 1) Ten leaves from the sample (for non-conifers) are immediately measured for spectral characteristics using a portable spectroradiometer with plant probe. These samples are then weighed using a portable balance, and scanned on a flatbed scanner for their area. These samples are then placed in a paper envelope for drying. (Note: conifer samples are often not measured with the spectroradiometer, but a set of twenty-five to fifty needles are scanned.) These samples are returned to Wisconsin, where they are oven dried and re-weighed to get dry mass as a basis for calculating foliar water content and LMA; 2) A small (under two grams) representative sample of foliage is flash frozen (in liquid N if available, otherwise, dry ice) and stored for later transport for chemical analyses. These samples are transferred to a freezer at the earliest convenience. This sample is returned to Wisconsin frozen. Part of the frozen samples is analyzed for labile constituents such as pigments, and the rest is later freeze dried and analyzed for constituents such as sugars, starches and phenolics; 3) The remaining sample is placed in a paper bag and allowed to air dry. These samples are transferred to Wisconsin, where they are oven dried, then later ground to 20-mesh. The samples are measured for dry spectra to estimate chemical traits, and a subset are sent for chemical analyses. At each site, approximately sixty to a hundred-and-twenty grams of fresh foliar material are sampled, measured in the field and then prepared for shipment to Wisconsin for further analyses. There are numerous possible activities. The team will take one to two students along on a research flight. The team may be able to give tours of the airplane and public talks on the research plans and activities. Members of the ABoVE science team will share all academic reports and articles associated with this campaign, and will put together fact sheets appropriate for a general audience. The research team anticipate scheduling community presentations in 2020, in conjunction with other NASA ABoVE project teams that are conducting field-based research (under other existing permits). The fieldwork for this study will be conducted from 1-Jul-2019 to 30-Sep-2019.