Small-Scale Decadal Change in Land Cover Near Barrow, Alaska
Josh Picotte, Craig E. Tweedie, Robert D. Hollister and Patrick J. WebberPolygonized Tundra:
- Polygonized tundra is common in coastal areas at high Northern latitudes2.
- Polygons form when cracks in the tundra fill with water and freeze, creating an 'ice wedge'. Over several years/decades and repetitive freezing and thawing, these ice wedges grow causing soil to be thrust upwards, forming a noticeable shoulder or 'polygon rim' in the process. Ice wedges between polygon rims form depressions termed 'troughs'. In some areas, the polygon rim can cause impoundment of water in the center of the polygon. When this occurs, the polygon is termed a 'low-centered polygon'3. Low-centered polygons surround the resampled grid.
- The subtle microtopographic variation associated with polygons result in large hydrological variation. Hydrology is the dominant factor influencing the distribution of vegetation in tundra4.
- Even a minor change in the microtopography or hydrology of polygonized tundra can cause a dramatic change in land cover.
- In the vicinity of the resampled grid, microtopographic and/or hydrological change could have occurred as a result of climate change and/or the artificial drainage of several large shallow lakes. Results of this study are interpreted in consideration of these.
- Beginning
- Introduction & Relevance
- Polygonized Tundra
- Methods
- Results
- Summary
- References