Biogeochemical processes in tundra soils: i) consequences of wildfires, and ii) greenhouse gas emissions in a contrasting landscape.
Two possible master projects are offered in the summer 2020.
One project investigates the effect of wildfires in Arctic tundra with particular attention to soil biogeochemical processes and vegetation changes. Tundrafires are increasingly abundant due to climate warming and altered precipitation in Arctic, and has detrimental effects on tundra ecosystems. We study fire effects on soil and vegetation carbon, nitrogen and phosphorus chemistry and turnover.
The second project focuses on the tundra soil CN processes along topographic and hydrological gradients in a contrasting landscape. This project has the main topic to quantify surface emissions of the greenhouse gases nitrous oxide and methane and identify key soil conditions responsible for the GHG activities in an attempt to upscale surface GHGs. Both projects combines fieldwork in the summer 2020 including deployment of state-of-the-art laser instruments to measure soil surface greenhouse gas emissions, observations of soil chemical and physical conditions, and climate. Samples of water, soil and vegetation are collected during the fieldwork and subsequently analyzed for C, N and P-contents and their isotopic compositions in the laboratory. The study site is located at Disko Island, close to Arctic Station, W Greenland.
Temporal and spatial development of permafrost under the influence of changed active layer thickness
This project investigates how permafrost thaw changes the routing and chemistry of water on a landscape scale. A manipulation experiment has been established and instrumented on a slope in Qaanaaq (77°N) in North Greenland to understand the effects of climate change and nutrient release from permafrost. The student will perform field work in Qaanaaq in summer 2019 and contribute to (1) collection, analysis and interpretation of water samples; (2) installation and monitoring of piezometers and frost tubes and (3) interaction with pupils from a local school in the form of a citizen science project.
Contact: Sebastian F. Zastruzny, firstname.lastname@example.org ; Bo Elberling, email@example.com
Climate gradients in the landscape and upscaling in relation to natural ecosystems in Greenland
The project is related to an installed instrument called "atmospheric profiles (RPG HATPRO), which soon has delivered data for 2 years and now provides a continuous date set of the vertical distribution of air masses, including air temperature, etc. Data is available for the thesis. The purpose of the project is to (1) validate vertical profile data against climate data from stations in the area located from sea level to a mountain peak, (2) quantify the duration and frequency of inversion layers with warm leak in the heights of Disko, and (3) connect climate gradients in part snow distribution and plant growth over time and space in a local context using medium and coarse spatial resolution remote sensing data. Planned stay in Nuuk and possibly field work on Disko (close cooperation and supervision from Asiaq).
Contact: Bo Elberling, firstname.lastname@example.org ; Birger Ulf Hansen, email@example.com
Monitoring spatiotemporal variations in soil wetness in an Arctic mountainous watershed using remote sensing data and digital elevation models
It is essential to accurately monitor the spatial and temporal variation of soil moisture in large Arctic watersheds to better understand hydrological processes. However, soil moisture exhibits significant variability in both space and time. Lately a modified topographic wetness index has been developed. The purpose of the project is to (1) validate and sophisticate the index by incorporating the spatiotemporal variation of the snow cover, (2) to quantify the seasonal variability of the soil moisture and (3) to estimate future variability in soil moisture due to climate change.
Contact: Birger Ulf Hansen, firstname.lastname@example.org
Monitoring local glaciers and ice caps spatiotemporal variations in soil wetness in an Arctic mountainous watershed
Recent worldwide observations show that local glaciers and ice caps (GIC) are responsible for approx. 25 % of the total global mean sea level rise. However, the sensitivity of GICs in Greenland to prolonged warm periods is less well constrained and new records documenting the long-term glacial history are needed to put recent observations into a broader perspective. In August 1863 the Danish geographer Johannes Rink camped in Kobbefjord and during his stay he took several landscape photos - some of the first photos taken in Greenland. These photos open the possibility to – (1) verify/validate the GIC-modeling on a much wider timescale, (2) expand the model to a wider area – Nuuk Fjord and (3) to give a qualified estimate on when the local GIC will disappear due to climate change.