Tree-ring investigations into changing climatic responses of yellow-cedar, Glacier Bay, Alaska

摘要: Yellow-cedar (Callitropsis nootkatensis (D. Don) Orsted ex D.P. Little) is in a century-long decline coinciding with the end of Little Ice Age (LIA). The leading hypothesis explaining this decrease insulating snowpack due to warming and increased susceptibility damaging frosts root zone. A ring-width series from yellow-cedar on Excursion Ridge (260 m a.s.l.) Glacier Bay National Park Preserve, Alaska, another trees Pleasant Island (150 Tongass Forest Icy Strait were compared regional monthly temperature precipita- tion data Sitka, investigate changing growth response at these sites. Comparisons temperatures 1832 1876 during show that high-elevation low-elevation sites strongly favored warmer January through July temperatures. Both tree populations have markedly changed their positive strong negative correlation tempera- tures since 1950. This by together relationship to- tal March April precipitation suggests may be susceptible decline. Furthermore, analyses are consistent linked decreased snowpack.