Spring Leaf Phenology: Discrepancies between in situ Observations and Satellite Data at Rural and Urban Sites in Ireland
Abstract
Spring phenophases, such as bud burst and leaf-out of temperate deciduous trees are important determinants of the start of the growing season and thus have a controlling influence on the timing of the carbon-uptake period. In order to accurately calculate forest carbon budgets, reliable start-of-season data over relatively large areas is necessary. Here we propose to examine trends (1968-2016) in in situ observations of the timing of leaf-out from a suite of deciduous trees at three rural sites and one urban site in Ireland, all of which are sites within the International Phenological Gardens network. We will compare these trends with satellite derived metrics including start of greening and peak greening based on two-band Enhanced Vegetation Index (EVI2) from AVHRR and MODIS over the time period 1982-2016. The aim of this study is to assess the effectiveness of satellite remote sensing in capturing spring phenology as determined by in situ observations from sites dominated by varying land cover types. We hypothesize that there will be discrepancies between direct observations and satellite measures of the timing of leaf-out which may vary according to a number of factors such as (i) scale (leaf vs landscape), (ii) surrounding land use type and (iii) uncertainty associated with what exactly the satellite is detecting. In addition, we anticipate that the urban site will be significantly different from the rural sites due, primarily, to the influence of the urban heat island. These results could highlight which land cover types are best represented by satellite-derived spring phenology.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.B11N2359D
- Keywords:
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- 0439 Ecosystems;
- structure and dynamics;
- BIOGEOSCIENCES;
- 0466 Modeling;
- BIOGEOSCIENCES;
- 0476 Plant ecology;
- BIOGEOSCIENCES;
- 0480 Remote sensing;
- BIOGEOSCIENCES