Zobrazeno 1 - 10
of 239
pro vyhledávání: '"J. Lemmetyinen"'
Publikováno v:
The Cryosphere, Vol 18, Pp 1561-1578 (2024)
Radar at high frequency is a promising technique for fine-resolution snow water equivalent (SWE) mapping. In this paper, we extend the Bayesian-based Algorithm for SWE Estimation (BASE) from passive to active microwave (AM) application and test it us
Externí odkaz:
https://doaj.org/article/b0b7de8944e24aab8a9e340e98ef69ce
Publikováno v:
The Cryosphere, Vol 18, Pp 869-888 (2024)
Monitoring of lake ice is important to maintain transportation routes, but in recent decades the number of in situ observations have declined. Remote sensing has worked to fill this gap in observations, with active microwave sensors, particularly syn
Externí odkaz:
https://doaj.org/article/267968b6a1d44951bfeb50290bea936a
Autor:
A. Mavrovic, O. Sonnentag, J. Lemmetyinen, C. Voigt, N. Rutter, P. Mann, J.-D. Sylvain, A. Roy
Publikováno v:
Biogeosciences, Vol 20, Pp 5087-5108 (2023)
The carbon cycle in Arctic–boreal regions (ABRs) is an important component of the planetary carbon balance, with growing concerns about the consequences of ABR warming for the global climate system. The greatest uncertainty in annual carbon dioxide
Externí odkaz:
https://doaj.org/article/57cb30ccf39547baad4350f3257e8f03
Publikováno v:
Biogeosciences, Vol 20, Pp 2941-2970 (2023)
Spaceborne microwave remote sensing (300 MHz–100 GHz) provides a valuable method for characterizing environmental changes, especially in Arctic–boreal regions (ABRs) where ground observations are generally spatially and temporally scarce. Althoug
Externí odkaz:
https://doaj.org/article/15d59d4ebcd6472482f256b9b5ae2ae8
Autor:
P. Venäläinen, K. Luojus, C. Mortimer, J. Lemmetyinen, J. Pulliainen, M. Takala, M. Moisander, L. Zschenderlein
Publikováno v:
The Cryosphere, Vol 17, Pp 719-736 (2023)
Snow water equivalent (SWE) is a valuable characteristic of snow cover, and it can be estimated using passive spaceborne radiometer measurements. The radiometer-based GlobSnow SWE retrieval methodology, which assimilates weather station snow depth ob
Externí odkaz:
https://doaj.org/article/7adfc8b98f544398b44dc317d9fc2a94
Autor:
J. Lemmetyinen, J. Cohen, A. Kontu, J. Vehviläinen, H.-R. Hannula, I. Merkouriadi, S. Scheiblauer, H. Rott, T. Nagler, E. Ripper, K. Elder, H.-P. Marshall, R. Fromm, M. Adams, C. Derksen, J. King, A. Meta, A. Coccia, N. Rutter, M. Sandells, G. Macelloni, E. Santi, M. Leduc-Leballeur, R. Essery, C. Menard, M. Kern
Publikováno v:
Earth System Science Data, Vol 14, Pp 3915-3945 (2022)
The European Space Agency SnowSAR instrument is a side-looking, dual-polarised (VV/VH), X/Ku band synthetic aperture radar (SAR), operable from various sizes of aircraft. Between 2010 and 2013, the instrument was deployed at several sites in Northern
Externí odkaz:
https://doaj.org/article/aaff034f91164fc18bd05d0a36bdcf85
Review article: Global monitoring of snow water equivalent using high-frequency radar remote sensing
Autor:
L. Tsang, M. Durand, C. Derksen, A. P. Barros, D.-H. Kang, H. Lievens, H.-P. Marshall, J. Zhu, J. Johnson, J. King, J. Lemmetyinen, M. Sandells, N. Rutter, P. Siqueira, A. Nolin, B. Osmanoglu, C. Vuyovich, E. Kim, D. Taylor, I. Merkouriadi, L. Brucker, M. Navari, M. Dumont, R. Kelly, R. S. Kim, T.-H. Liao, F. Borah, X. Xu
Publikováno v:
The Cryosphere, Vol 16, Pp 3531-3573 (2022)
Seasonal snow cover is the largest single component of the cryosphere in areal extent, covering an average of 46 × 106 km2 of Earth's surface (31 % of the land area) each year, and is thus an important expression and driver of the Earth's climate. I
Externí odkaz:
https://doaj.org/article/3fc8bc82560543a6b98ee097709577ea
Publikováno v:
Earth System Science Data, Vol 13, Pp 3967-3978 (2021)
Climate change and global warming strongly impact the cryosphere. The rise of air temperature and change of precipitation patterns lead to dramatic responses of snow and ice heat and mass balance. Sustainable field observations on lake air–snow–i
Externí odkaz:
https://doaj.org/article/1c672cf893d14aa9ac868597c4147bee
Publikováno v:
The Cryosphere, Vol 15, Pp 2969-2981 (2021)
Snow water equivalent (SWE) is an important variable in describing global seasonal snow cover. Traditionally, SWE has been measured manually at snow transects or using observations from weather stations. However, these measurements have a poor spatia
Externí odkaz:
https://doaj.org/article/b6a54b73067549bd84741f4f9dc2bf1c
Publikováno v:
The Cryosphere, Vol 14, Pp 1763-1778 (2020)
We investigated the potential capability of the random forest (RF) machine learning (ML) model to estimate snow depth in this work. Four combinations composed of critical predictor variables were used to train the RF model. Then, we utilized three va
Externí odkaz:
https://doaj.org/article/01239cb620e341f093e290ab76fb50cb