Projects per year
Abstract
Uncertainties in estimation of albedo-related radiative forcing cause ambiguity in evaluation of net climate effects of forests and forest management. Numerous studies have reported local relations between forest structure and albedo in the boreal zone. However, more research is needed to establish these relations for geographically extensive areas, and to examine seasonal courses of albedo to understand the effects of forest structure on mean annual shortwave energy balance. Remote sensing is a viable option for accomplishing these goals, but there are many challenges related to e.g. long periods of cloud cover and low solar elevations in high latitudes. We used the new MODIS Collection 6 (MCD43A3) daily albedo product, and analyzed MODIS albedo dependence on airborne LiDAR-based forest structure in 22 study sites in Estonia, Finland, Sweden, and Russia (57°–69° N, 12°–57° E). Wall-to-wall LiDAR data allowed us to take into account the effective spatial resolution of MODIS, which notably improved correlations between albedo and forest structure. Use of the best quality backup algorithm (magnitude inversion) together with main algorithm results in the MODIS albedo product did not reduce the correlations compared to using main algorithm only. We quantified the effects of landscape-level forest structure (forest height, canopy cover, fraction of young forest) and fraction of broadleaved deciduous forest on mean annual albedo. We showed that because the forest structure-albedo relations are the strongest in snow-covered periods, and because the snow-covered period is longest in the north, the effect of forest structure on mean annual albedo increases towards the north. On the other hand, the effect of broadleaved fraction did not show such latitudinal trend. Our results indicate that even within a single climatic zone the optimal forest management solution to mitigate climate change depends on geographic location.
Original language | English |
---|---|
Pages (from-to) | 365-381 |
Number of pages | 17 |
Journal | Remote Sensing of Environment |
Volume | 224 |
DOIs | |
Publication status | Published - 1 Apr 2019 |
MoE publication type | A1 Journal article-refereed |
Keywords
- Albedo
- Boreal forests
- Forest management
- MODIS
- Seasonality
- COVER
- LAND-SURFACE ALBEDO
- SNOW
- VALIDATION
- MODEL
- OPERATIONAL BRDF
- RADIATION
- NADIR REFLECTANCE PRODUCTS
Fingerprint
Dive into the research topics of 'Seasonal dynamics of albedo across European boreal forests : Analysis of MODIS albedo and structural metrics from airborne LiDAR'. Together they form a unique fingerprint.Projects
- 2 Finished
-
FREEDLES: From needles to landscapes: a novel approach to scaling forest spectra
Rautiainen, M. (Principal investigator), Hovi, A. (Project Member), Juola, J. (Project Member), Mercier, A. (Project Member), Salko, S.-S. (Project Member), Rönkkö, J. (Project Member), Karlqvist, S. (Project Member) & Schraik, D. (Project Member)
01/05/2018 → 30/04/2024
Project: EU: ERC grants
-
BOREALITY: Seasonal dynamics of the boreal region from space: connecting forest albedo to structure and productivity throughout the phenological cycle
Hovi, A. (Project Member), Rautiainen, M. (Principal investigator), Majasalmi, T. (Project Member), Juola, J. (Project Member) & Palviainen, P. (Project Member)
01/09/2015 → 31/12/2019
Project: Academy of Finland: Other research funding
Equipment
-
i3 – Industry Innovation Infrastructure
Sainio, P. (Manager)
School of EngineeringFacility/equipment: Facility
-
Spectral lab (i3)
Rautiainen, M. (Manager)
Department of Built EnvironmentFacility/equipment: Facility