Appendix A. Supplementary study site information, including photographs, bathometric maps and coring locations, and modern vegetation and climate for Raven, Uchugrak, Poktovik, and Little Isac lakes.
FIG. A1. Landscape and vegetation surrounding each lake in the Noatak study area. (A) Raven Lake, looking north/northwest, (B) Uchugrak Lake from the southern hillside, (C) Poktovik Lake, looking southwest towards the Noatak River, and (D) Little Isac Lake, looking north towards the Isacheluich Mountains. Photo credit: P. Higuera.
FIG. A2. Bathometric maps of study lakes. The approximate coring location is indicated by the white circle.
FIG. A3. Modern climate variables within approximately four km of each lake. Mean growing season (June–August) temperature (A), estimated potential evapotranspiration (PET; B), precipitation (C), and estimated actual evapotranspiration (AET; D) are from the 2-km resolution Parameter-elevation Regression on Independent Slopes Model (PRISM; Daly et al. 1994), as displayed in Fig. 1 in the main text. Boxplots display the 10th, 25th, 50th, 75th, and 90th quartiles, with outliers as black dots, based on 25 2-km pixels that include and surround each lake. AET and PET estimates are from the temperature-based model of Thornthwaite, as described by Willmott et al. (1985). PET estimates were calculated using a single available water capacity of 50 mm, and among-site patterns in PET were robust to available water capacities.
FIG. A4. Modern vegetation around study lakes. Distances refer to the radius around each lake. Vegetation classification is based on (Jorgenson et al. 2009).
Daly, C., R. P. Neilson, and D. L. Phillips. 1994. A Statistical Topographic Model for Mapping Climatological Precipitation over Mountainous Terrain. Journal of Applied Meteorology 33:140–158.
Jorgenson, M. T., J. E. Roth, P. F. Miller, M. J. Macander, M. S. Duffy, A. F. Wells, G. V. Frost, and E. R. Pullman. 2009. An ecological land survey and landcover map of the Arctic Network. NPS/ARCN/NRTR—2009/270, National Park Service, Fort Collins, Colorado, USA.
Willmott, C. J., C. M. Rowe, and Y. Mintz. 1985. Climatology of the terrestrial seasonal water cycle. Journal of Climatology 5:589–606.