Unexpected extreme events drive the inter-annual variability in carbon exchange at the pine forest in Netherlands
Student name: Ms Sanjna Sethi
Guide: Dr Chubamenla Jamir
Year of completion: 2017
Host Organisation: The Energy and Resource Institute (TERI), New Delhi
Supervisor (Host Organisation): Dr Ir. Eddy Moors
Abstract: The carbon exchange between vegetation and the atmosphere tends to vary on an
annual basis. This change is a continuous process and its trend emerging over a
period of years can be analysed. In any such trend, recorded over a prolonged
period, some years stand out more than the others. Explaining deviations from the
expected average emissions may help us understand the drivers behind these inter-
annual deviations. Such noticeable deviations in trend maybe on account of
extreme events, and need to be analysed in overall context of the ecosystem. This
research’s focus is to identify the main drivers responsible for the deviations, and
how extreme events impact the variability over a prolonged period of time. The
hypothesis being that extreme events are driving these deviations. Carbon flux
data done for multiple years (1997-2015) for a site at the Loobos Pine Forest is
used and compared with an ecosystem model, LPJ-GUESS (Lund–Potsdam–Jena
General Ecosystem Simulator) to understand if the deviation of measured data
from the simulated data is on account of extreme events on a monthly and daily
basis. A Principal Component Analysis is performed on the identified deviations
between measured and simulated carbon exchange to pin point the main cause
behind their occurrence.
Keywords: Forests, Inter-annual variability, Extreme events, carbon fluxes, net
ecosystem exchange and drought.
