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of temperate coniferous forests—Relationship with Leaf-Area Index. Remote Sens. Environ. 33 : 97 – 112 . Steinberg , D. C. , S. J. Goetz , and E. Hyer . 2006 . Validation of MODIS Fpar products in boreal forests of Alaska. IEEE Trans. Geosci. Remote Sens. in press . Sturm , M. , J. P. McFadden , G. E. Liston , F. S. Chapin , C. H. Racine , and J. Holmgren . 2001 . Snow–shrub interactions in arctic tundra: A hypothesis with climatic implications. J. Climate
of temperate coniferous forests—Relationship with Leaf-Area Index. Remote Sens. Environ. 33 : 97 – 112 . Steinberg , D. C. , S. J. Goetz , and E. Hyer . 2006 . Validation of MODIS Fpar products in boreal forests of Alaska. IEEE Trans. Geosci. Remote Sens. in press . Sturm , M. , J. P. McFadden , G. E. Liston , F. S. Chapin , C. H. Racine , and J. Holmgren . 2001 . Snow–shrub interactions in arctic tundra: A hypothesis with climatic implications. J. Climate
-shrubs, grasses,mosses and lichens of the tundra grow. In the case ofa cooling, the trees of taiga die when exposed to temperatures lower than the acceptable range for theirhabitat; the roots decay and wind topples the trees.The arctic plants take over, that is, the tundra expandssouthward.We now simulate the climate sensitivity to the solarconstant by placing the taiga/tundra ecocline at thelatitude where the average surface temperature is -5°C.The results are presented in Table 2, columns 8 and9. The
-shrubs, grasses,mosses and lichens of the tundra grow. In the case ofa cooling, the trees of taiga die when exposed to temperatures lower than the acceptable range for theirhabitat; the roots decay and wind topples the trees.The arctic plants take over, that is, the tundra expandssouthward.We now simulate the climate sensitivity to the solarconstant by placing the taiga/tundra ecocline at thelatitude where the average surface temperature is -5°C.The results are presented in Table 2, columns 8 and9. The
. Krebs , S. J. , and R. G. Barry , 1970 : The Arctic front and the tundra-taiga boundary in Eurasia. Geogr. Rev , 60 , 548 – 554 . Kurashima , A. , 1968 : Studies on the summer and winter monsoons in east Asia based on dynamic concept. Geogr. Mag , 34 , 145 – 236 . Lucht , W. , and Coauthors , 2002 : Climatic control of the high-latitude vegetation greening trend and Pinatubo effect. Science , 296 , 1687 – 1689 . Lynch , A. H. , A. G. Salter , and M. Serreze , 2001
. Krebs , S. J. , and R. G. Barry , 1970 : The Arctic front and the tundra-taiga boundary in Eurasia. Geogr. Rev , 60 , 548 – 554 . Kurashima , A. , 1968 : Studies on the summer and winter monsoons in east Asia based on dynamic concept. Geogr. Mag , 34 , 145 – 236 . Lucht , W. , and Coauthors , 2002 : Climatic control of the high-latitude vegetation greening trend and Pinatubo effect. Science , 296 , 1687 – 1689 . Lynch , A. H. , A. G. Salter , and M. Serreze , 2001
various models are compared for typical stratuscloud conditions in the Arctic summer. He calculatedthat, under cloudy conditions, incident solar radiationcould be increased on the order of 30% when the surfacealbedo is increased from 20 to 79%. Holmgren andWeller (1973) in a study at Point Barrow, Alaska, foundthat, for 6 days in April over the snow-covered tundra,incoming solar radiation at the surface only decreasedby about 15% when a cloud cover formed. This wasdue to the enhancement by multiple
various models are compared for typical stratuscloud conditions in the Arctic summer. He calculatedthat, under cloudy conditions, incident solar radiationcould be increased on the order of 30% when the surfacealbedo is increased from 20 to 79%. Holmgren andWeller (1973) in a study at Point Barrow, Alaska, foundthat, for 6 days in April over the snow-covered tundra,incoming solar radiation at the surface only decreasedby about 15% when a cloud cover formed. This wasdue to the enhancement by multiple
Alaskan tundra was used to develop the approach boundary-layer profile. The observed dispersion with nobuildings present was near the values expected for classD (neutral) in the Pasquill-Gifford (PG) stability classification system. Our arctic field measurements(Guenther and Lamb 1989) suggest that the wind tunnel model provided a reasonable approximation of thewintertime arctic boundary layer. The 1 to 250 scale model used in the wind tunnelwas constructed with building and landscape
Alaskan tundra was used to develop the approach boundary-layer profile. The observed dispersion with nobuildings present was near the values expected for classD (neutral) in the Pasquill-Gifford (PG) stability classification system. Our arctic field measurements(Guenther and Lamb 1989) suggest that the wind tunnel model provided a reasonable approximation of thewintertime arctic boundary layer. The 1 to 250 scale model used in the wind tunnelwas constructed with building and landscape
: Holocene vegetation histories from three sites in the tundra of northwestern Quebec, Canada. Arct. Alp. Res. , 24 , 329 – 336 . Gajewski , K. , and G. M. MacDonald , 2004 : Palynology of North American Arctic Lakes. Long-Term Environmental Change in Arctic and Antarctic Lakes , R. Pienitz, M. S. V. Douglas, and J. P. Smol, Eds., Springer, 89–116 . Gajewski , K. , S. Payette , and J. C. Ritchie , 1993 : Holocene vegetation history at the boreal-forest–shrub-tundra transition in
: Holocene vegetation histories from three sites in the tundra of northwestern Quebec, Canada. Arct. Alp. Res. , 24 , 329 – 336 . Gajewski , K. , and G. M. MacDonald , 2004 : Palynology of North American Arctic Lakes. Long-Term Environmental Change in Arctic and Antarctic Lakes , R. Pienitz, M. S. V. Douglas, and J. P. Smol, Eds., Springer, 89–116 . Gajewski , K. , S. Payette , and J. C. Ritchie , 1993 : Holocene vegetation history at the boreal-forest–shrub-tundra transition in
relation to climate. Rand Report R-444-PR, Rand Corp., Santa Monica, CA, 179 pp.Foster, J. L., 1989: The significance of the date of snow disappearance on the Arctic tundra as a possible indicator of climatic change. Arct. Alp. Res., 21, 60-70.Gross, C. E., 1986: Joint Ice Center global sea ice digital data. Snow Watch '85, G. Kulda, R. G. Barry, A. Hecht and D. Wiesnet, Eds., Glaciological Data GD-18, World Data Center for Gla ciology, Boulder, CO 80309, 125-126.Hansen, J., and S. Lebedeff
relation to climate. Rand Report R-444-PR, Rand Corp., Santa Monica, CA, 179 pp.Foster, J. L., 1989: The significance of the date of snow disappearance on the Arctic tundra as a possible indicator of climatic change. Arct. Alp. Res., 21, 60-70.Gross, C. E., 1986: Joint Ice Center global sea ice digital data. Snow Watch '85, G. Kulda, R. G. Barry, A. Hecht and D. Wiesnet, Eds., Glaciological Data GD-18, World Data Center for Gla ciology, Boulder, CO 80309, 125-126.Hansen, J., and S. Lebedeff
regional meteorology. Mon. Wea. Rev. , 117 , 2113 – 2136 . 10.1175/1520-0493(1989)117<2113:APOHLS>2.0.CO;2 Bewley, D. , 2006 : Shrub-tundra effects on snowmelt energectics and the atmospheric interaction with snow. Ph.D. thesis, University of Wales, Aberystwyth, Wales, 211 pp . Bewley, D. , Pomeroy J. W. , and Essery R. L. H. , 2007 : Solar radiation transfer through a sub-arctic shrub canopy. Arct. Alp. Res. , 39 , 365 – 374 . 10.1657/1523-0430(06-023)[BEWLEY]2.0.CO;2 Carey, S. K
regional meteorology. Mon. Wea. Rev. , 117 , 2113 – 2136 . 10.1175/1520-0493(1989)117<2113:APOHLS>2.0.CO;2 Bewley, D. , 2006 : Shrub-tundra effects on snowmelt energectics and the atmospheric interaction with snow. Ph.D. thesis, University of Wales, Aberystwyth, Wales, 211 pp . Bewley, D. , Pomeroy J. W. , and Essery R. L. H. , 2007 : Solar radiation transfer through a sub-arctic shrub canopy. Arct. Alp. Res. , 39 , 365 – 374 . 10.1657/1523-0430(06-023)[BEWLEY]2.0.CO;2 Carey, S. K
1. Introduction Due to Arctic warming, shrub abundance and height are increasing in the tundra ( Tape et al. 2006 ; Myers-Smith et al. 2011 ; Ropars and Boudreau 2012 ; Tremblay et al. 2012 ; Lemay et al. 2018 ), which greatly darkens snowy winter surfaces when shrub branches protrude above the snow ( Sturm et al. 2005 ; Loranty et al. 2011 ; Ménard et al. 2014b ). The resulting albedo reduction potentially feeds back into regional and global climate through increases in air temperature
1. Introduction Due to Arctic warming, shrub abundance and height are increasing in the tundra ( Tape et al. 2006 ; Myers-Smith et al. 2011 ; Ropars and Boudreau 2012 ; Tremblay et al. 2012 ; Lemay et al. 2018 ), which greatly darkens snowy winter surfaces when shrub branches protrude above the snow ( Sturm et al. 2005 ; Loranty et al. 2011 ; Ménard et al. 2014b ). The resulting albedo reduction potentially feeds back into regional and global climate through increases in air temperature
surrounding the names we used. For example, the Tundra class was meant to evoke an image of snow in cold, dry, windswept areas located on top of low-stature vegetation in high-latitude and high-elevation environments. The associated snow would consist of alternating layers of wind slab and depth hoar, be quite thin (<0.8 m), and would include surface features such as dunes, barchans, and sastrugi created by the wind. Such snow would be found in Arctic tundra regions, but it could also be found near or on
surrounding the names we used. For example, the Tundra class was meant to evoke an image of snow in cold, dry, windswept areas located on top of low-stature vegetation in high-latitude and high-elevation environments. The associated snow would consist of alternating layers of wind slab and depth hoar, be quite thin (<0.8 m), and would include surface features such as dunes, barchans, and sastrugi created by the wind. Such snow would be found in Arctic tundra regions, but it could also be found near or on
