Improving UK greenhouse gas emission estimates using tall tower observations
View/ Open
Date
30/06/2014Author
Howie, James Edward
Metadata
Abstract
Greenhouse gases in the Earth’s atmosphere play an important role in regulating
surface temperatures. The UK is signatory to international agreements that legally
commit the UK to reduce its greenhouse gas emissions, and there is a scientific and
political need to better understand greenhouse gas sources on regional scales. The current
methods used to provide greenhouse gas emission inventories rely on ‘bottom-up’
techniques and have large associated errors. However, it is also possible to use observations
of atmospheric concentrations of greenhouse gases and models of atmospheric
transport to link the observations with source regions in order to estimate emissions
in a ‘top-down’ approach. The key findings presented in this thesis are (a) UK emissions
can be retrieved from the Angus tall tower in Scotland using the NAME inversion
technique at a finer spatial resolution than has previously been reported using similar
‘top-down’ inverse methods; (b) atmospheric measurements from the Angus tall tower
in Scotland have been used for the first time with the NAME inversion technique in
order to estimate UK emissions of methane, nitrous oxide and sulfur hexafluoride for
the years 2006 to 2009; (c) increasing the number of towers in UK network substantially
increases the spatial resolution of greenhouse gas emission estimates. The errors
and uncertainties associated with the NAME inversion over the UK domain are discussed
and potential future improvements to this approach are presented. Overall, the
work presented in this thesis has contributed to our understanding of the spatial and
inter-annual variability of UK greenhouse gas emissions.