Martin Wilmking

TL;DR: This article used repeat photography, long-term ecological monitoring and dendrochronology to document shrub expansion in arctic, high-latitude and alpine tundra.

TL;DR: In this paper, the authors systematically sampled 1558 white spruce at 13 treeline sites in the Brooks Range and Alaska Range and found that high mean temperatures in July decreased the growth of 40% of treeline areas in Alaska, whereas warm springs enhance growth of additional 36% of trees and 24% show no significant correlation with climate.

TL;DR: In this article, the authors analyzed circumpolar data from 37 Arctic and alpine sites in 9 countries, including 25 species, and ∼42,000 annual growth records from 1,821 individuals, and demonstrated that the sensitivity of shrub growth to climate was heterogeneous, with European sites showing greater summer temperature sensitivity than North American sites, and higher at sites with greater soil moisture and for taller shrubs (for example, alders and willows) growing at their northern or upper elevational range edges.

TL;DR: Biome-wide relationships between temperature, moisture and seven key plant functional traits across the tundra and over time show that community height increased with warming across all sites, whereas other traits lagged behind predicted rates of change.

TL;DR: In this paper, a consensus is emerging that the underlying causes and future dynamics of so-called Arctic greening and browning trends are more complex, variable and inherently scale-dependent than previously thought.