Search Results - "Schaaf, Crystal L."

Carbon response of tundra ecosystems to advancing greenup and snowmelt in Alaska by Kim, JiHyun, Kim, Yeonjoo, Zona, Donatella, Oechel, Walter, Park, Sang-Jong, Lee, Bang-Yong, Yi, Yonghong, Erb, Angela, Schaaf, Crystal L.

“…The ongoing disproportionate increases in temperature and precipitation over the Arctic region may greatly alter the latitudinal gradients in greenup and…”
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Measuring effective leaf area index, foliage profile, and stand height in New England forest stands using a full-waveform ground-based lidar by Zhao, Feng, Yang, Xiaoyuan, Schull, Mitchell A., Román-Colón, Miguel O., Yao, Tian, Wang, Zhuosen, Zhang, Qingling, Jupp, David L.B., Lovell, Jenny L., Culvenor, Darius S., Newnham, Glenn J., Richardson, Andrew D., Ni-Meister, Wenge, Schaaf, Crystal L., Woodcock, Curtis E., Strahler, Alan H.

“…Effective leaf area index (LAI) retrievals from a scanning, ground-based, near-infrared (1064 nm) lidar that digitizes the full return waveform, the Echidna…”
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Quantifying the effects of freeze-thaw transitions and snowpack melt on land surface albedo and energy exchange over Alaska and Western Canada by Kim, Youngwook, Kimball, John S, Du, Jinyang, Schaaf, Crystal L B, Kirchner, Peter B

“…Variations in land surface albedo and snow-cover strongly impact the global biosphere, particularly through the snow-albedo feedback on climate. The seasonal…”
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Developing a spatially continuous 1 km surface albedo data set over North America from Terra MODIS products by Fang, Hongliang, Liang, Shunlin, Kim, Hye-Yun, Townshend, John R., Schaaf, Crystal L., Strahler, Alan H., Dickinson, Robert E.

“…Surface albedo is an important factor governing the surface radiation budget and is critical in modeling the exchange of energy, water and carbon between Earth…”
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Deriving and validating Leaf Area Index (LAI) at multiple spatial scales through lidar remote sensing: A case study in Sierra National Forest, CA by Tang, Hao, Brolly, Matthew, Zhao, Feng, Strahler, Alan H., Schaaf, Crystal L., Ganguly, Sangram, Zhang, Gong, Dubayah, Ralph

“…Increasing the accuracy and spatial coverage of Leaf Area Index (LAI) values is an important part of any attempt to successfully model global…”
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Increased water yield due to the hemlock woolly adelgid infestation in New England by Kim, Jihyun, Hwang, Taehee, Schaaf, Crystal L., Orwig, David A., Boose, Emery, Munger, J. William

“…Over the past few decades, a hemlock woolly adelgid (HWA) infestation has significantly affected eastern hemlock (Tsuga canadensis) in the eastern U.S., and…”
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Seasonal variation of source contributions to eddy-covariance CO2 measurements in a mixed hardwood-conifer forest by Kim, JiHyun, Hwang, Taehee, Schaaf, Crystal L., Kljun, Natascha, Munger, J. William

“…•The source contribution to eddy-covariance CO2 data differed between leaf development stages.•The variation in the daytime CO2 data was accounted for by the…”
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Climate change decreases the cooling effect from postfire albedo in boreal North America by Potter, Stefano, Solvik, Kylen, Erb, Angela, Goetz, Scott J., Johnstone, Jill F., Mack, Michelle C., Randerson, James T., Román, Miguel O., Schaaf, Crystal L., Turetsky, Merritt R., Veraverbeke, Sander, Walker, Xanthe J., Wang, Zhuosen, Massey, Richard, Rogers, Brendan M.

“…Fire is a primary disturbance in boreal forests and generates both positive and negative climate forcings. The influence of fire on surface albedo is a…”
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Evaluation of Moderate Resolution Imaging Spectroradiometer land surface visible and shortwave albedo products at FLUXNET sites by Wang, Kaicun, Liang, Shunlin, Schaaf, Crystal L., Strahler, Alan H.

“…We evaluated the accuracy of Moderate Resolution Imaging Spectroradiometer (MODIS) Collections 4 and 5 shortwave and visible albedo products at 18 FLUXNET…”
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Warming‐Induced Earlier Greenup Leads to Reduced Stream Discharge in a Temperate Mixed Forest Catchment by Kim, Ji Hyun, Hwang, Taehee, Yang, Yun, Schaaf, Crystal L., Boose, Emery, Munger, J. William

“…The phenological response of vegetation to ongoing climate change may have great implications for hydrological regimes in the eastern United States. However,…”
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Measuring gap fraction, element clumping index and LAI in Sierra Forest stands using a full-waveform ground-based lidar by Zhao, Feng, Strahler, Alan H., Schaaf, Crystal L., Yao, Tian, Yang, Xiaoyuan, Wang, Zhuosen, Schull, Mitchell A., Román, Miguel O., Woodcock, Curtis E., Olofsson, Pontus, Ni-Meister, Wenge, Jupp, David L.B., Lovell, Jenny L., Culvenor, Darius S., Newnham, Glenn J.

“…The Echidna Validation Instrument (EVI), a ground-based, near-infrared (1064nm) scanning lidar, provides gap fraction measurements, element clumping index…”
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Assessment of biases in MODIS surface reflectance due to Lambertian approximation by Wang, Yujie, Lyapustin, Alexei I., Privette, Jeffrey L., Cook, Robert B., SanthanaVannan, Suresh K., Vermote, Eric F., Schaaf, Crystal L.

“…Using MODIS data and the AERONET-based Surface Reflectance Validation Network (ASRVN), this work studies errors of MODIS atmospheric correction caused by the…”
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Changes in tall shrub abundance on the North Slope of Alaska, 2000–2010 by Duchesne, Rocio R., Chopping, Mark J., Tape, Ken D., Wang, Zhuosen, Schaaf, Crystal L.B.

“…Mapping canopy-forming shrubs in tundra is challenging because approaches that rely on spectral information alone struggle to differentiate low and tall…”
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A comparison of foliage profiles in the Sierra National Forest obtained with a full-waveform under-canopy EVI lidar system with the foliage profiles obtained with an airborne full-waveform LVIS lidar system by Zhao, Feng, Yang, Xiaoyuan, Strahler, Alan H., Schaaf, Crystal L., Yao, Tian, Wang, Zhuosen, Román, Miguel O., Woodcock, Curtis E., Ni-Meister, Wenge, Jupp, David L.B., Lovell, Jenny L., Culvenor, Darius S., Newnham, Glenn J., Tang, Hao, Dubayah, Ralph O.

“…Foliage profiles retrieved from a scanning, terrestrial, near-infrared (1064nm), full-waveform lidar, the Echidna Validation Instrument (EVI), agree well with…”
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Simulation of Dissolved Organic Carbon Flux in the Penobscot Watershed, Maine by Rouhani, Shabnam, Schaaf, Crystal L., Huntington, Thomas G., Choate, Janet

“…Dissolved organic carbon (DOC) is an important component of the carbon cycle as a measure of the hydrological transport of carbon between terrestrial carbon…”
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Definition and measurement of tree cover: A comparative analysis of field-, lidar- and landsat-based tree cover estimations in the Sierra national forests, USA by Tang, Hao, Song, Xiao-Peng, Zhao, Feng A., Strahler, Alan H., Schaaf, Crystal L., Goetz, Scott, Huang, Chengquan, Hansen, Matthew C., Dubayah, Ralph

“…•Both definitional difference and estimation error affect tree cover mapping.•Three specified tree cover definitions linked to different remote sensing…”
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Finding Leaves in the Forest: The Dual-Wavelength Echidna Lidar by Douglas, Ewan S., Martel, Jason, Zhan Li, Howe, Glenn, Hewawasam, Kuravi, Marshall, Robert A., Schaaf, Crystal L., Cook, Timothy A., Newnham, Glenn J., Strahler, Alan, Chakrabarti, Supriya

“…The dual-wavelength Echidna lidar is a portable ground-based full-waveform terrestrial scanning lidar for characterization of fine-scale forest structure and…”
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Measuring effective leaf area index, foliage profile, and stand height in New England forest stands using a full-waveform ground-based lidar: DESDynnI VEG-3D Special Issue by FENG ZHAO, XIAOYUAN YANG, NEWNHAM, Glenn J, RICHARDSON, Andrew D, NI-MEISTER, Wenge, SCHAAF, Crystal L, WOODCOCK, Curtis E, STRAHLER, Alan H, SCHULL, Mitchell A, ROMAN-COLON, Miguel O, TIAN YAO, ZHUOSEN WANG, QINGLING ZHANG, JUPP, David L. B, LOVELL, Jenny L, CULVENOR, Darius S

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