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Abstract Vegetation phenology is a key control on water, energy, and carbon fluxes in terrestrial ecosystems. Because vegetation canopies are heterogeneous, spatially explicit information related to seasonality in vegetation activity provides valuable information for studies that use eddy covariance measurements to study ecosystem function and land-atmosphere interactions. Here we present a land surface phenology (LSP) dataset derived at 3 m spatial resolution from PlanetScope imagery across a range of plant functional types and climates in North America. The dataset provides spatially explicit information related to the timing of phenophase changes such as the start, peak, and end of vegetation activity, along with vegetation index metrics and associated quality assurance flags for the growing seasons of 2017–2021 for 10 × 10 km windows centred over 104 eddy covariance towers at AmeriFlux and National Ecological Observatory Network (NEON) sites. These LSP data can be used to analyse processes controlling the seasonality of ecosystem-scale carbon, water, and energy fluxes, to evaluate predictions from land surface models, and to assess satellite-based LSP products.
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Land–atmosphere interactions in the tropics – a review
Abstract. The continental tropics play a leading role in the terrestrial energy,water, and carbon cycles. Land–atmosphere interactions are integral in theregulation of these fluxes across multiple spatial and temporal scales overtropical continents. We review here some of the important characteristics oftropical continental climates and how land–atmosphere interactions regulatethem. Along with a wide range of climates, the tropics manifest a diversearray of land–atmosphere interactions. Broadly speaking, in tropicalrainforest climates, light and energy are typically more limiting thanprecipitation and water supply for photosynthesis and evapotranspiration (ET),whereas in savanna and semi-arid climates, water is the critical regulatorof surface fluxes and land–atmosphere interactions. We discuss the impact ofthe land surface, how it affects shallow and deep clouds, and how theseclouds in turn can feed back to the surface by modulating surface radiationand precipitation. Some results from recent research suggest that shallowclouds may be especially critical to land–atmosphere interactions. On theother hand, the impact of land-surface conditions on deep convection appearsto occur over larger, nonlocal scales and may be a more relevantland–atmosphere feedback mechanism in transitional dry-to-wet regions andclimate regimes.
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- Award ID(s):
- 1734156
- PAR ID:
- 10196573
- Date Published:
- Journal Name:
- Hydrology and Earth System Sciences
- Volume:
- 23
- Issue:
- 10
- ISSN:
- 1607-7938
- Page Range / eLocation ID:
- 4171 to 4197
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.5194/hess-23-4171-2019
