Vegetation type is an important predictor of the arctic summer land surface energy budget

Abstract

Despite the importance of high-latitude surface energy budgets (SEBs) for land-climate interactions in the rapidly changing Arctic, uncertainties in their prediction persist. Here, we harmonize SEB observations across a network of vegetated and glaciated sites at circumpolar scale (1994–2021). Our variance-partitioning analysis identifies vegetation type as an important predictor for SEB-components during Arctic summer (June-August), compared to other SEB-drivers including climate, latitude and permafrost characteristics. Differences among vegetation types can be of similar magnitude as between vegetation and glacier surfaces and are especially high for summer sensible and latent heat fluxes. The timing of SEB-flux summer-regimes (when daily mean values exceed 0 Wm−2) relative to snow-free and -onset dates varies substantially depending on vegetation type, implying vegetation controls on snow-cover and SEB-flux seasonality. Our results indicate complex shifts in surface energy fluxes with land-cover transitions and a lengthening summer season, and highlight the potential for improving future Earth system models via a refined representation of Arctic vegetation types.

Climate regulation processes are linked to the functional composition of plant communities in European forests, shrublands, and grasslands

“…ties. Yet, as often observed in ecology, the strength and direction of the resulting trait-CRP relationship depended on the CRP and the habitat type investigated (e.g., Alibakhshi et al, 2020;Kambach et al, 2023;Oehri et al, 2022).…”

“…Previous studies on the relationships between plant traits and CRPs have shown that albedo, which quantifies the proportion of reflected irradiation, differs between habitat types (Leonardi et al., 2015; Oehri et al., 2022) and is related to the tree cover, leaf reflectance, and the leaf area index (i.e., the summed area of green leaves per unit of ground area, Alibakhshi et al., 2020; Ridgwell et al., 2009) as well as the amount of plant litter in forest habitats (Serna‐Chavez et al., 2017). Evapotranspiration, which is the sum of plant transpiration and evaporation from the land surface, is related to plant hydraulic strategies (Matheny et al., 2017), total plant cover, rooting depth and, potentially, the canopy height of plant communities (Gates & Hanks, 1967).…”

“…Net primary productivity, which quantifies the amount of carbon captured minus maintenance costs, differs between habitat types (Harper et al, 2016) and is related to the specific leaf area and leaf nitrogen, phosphorus, and chlorophyll content (He et al, 2023) as well as the carbon pool in the different layers of forest habitats (Serna-Chavez et al, 2017). In summary, the impact of plant communities on local CRPs has been estimated to be of comparable magnitude to the impact of local climatic conditions on CRPs (Oehri et al, 2022;Serna-Chavez et al, 2017). Yet, most of the present findings are based on simulation and studies that covered a restricted number of habitat types or geographic extents.…”

Alleviated WRF Summer Wet Bias Over the Tibetan Plateau Using a New Cloud Macrophysics Scheme

“…A surface energy budget was conducted following previous studies (Chen et al., 2019; Oehri et al., 2022; Sellers et al., 1997). The surface energy budget consists of the most relevant components: $$${R}_{n}=\text{NSW}+\text{NLW}=\text{SH}+\text{LH}-\text{GH}$$$ where R n is the net radiative flux absorbed by the earth's surface, balanced by sensible heat flux (SH), latent heat flux (LH), and ground heat flux (GH).…”

“…A surface energy budget was conducted following previous studies (Chen et al, 2019;Oehri et al, 2022;Sellers et al, 1997). The surface energy budget consists of the most relevant components:…”