Development of a Dynamic Linear Model Procedure for Quantifying Long-term Trends in Atmospheric Time Series
Date
2020-06-21
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
0000-0001-6058-021X
Type
Thesis
Degree Level
Masters
Abstract
With satellite remote sensing instruments, global data records of various atmospheric
species, spanning considerable periods of time, have been produced. These data provide
insight into atmospheric processes and the evolution of our atmosphere. Statistical analysis
on them is essential. One thing in particular that we often wish to know about is the long-term
trend in a species concentration on the order of decades. This is important because it
allows us to monitor changes in our atmosphere. Changes that can be traced back to human
activity, giving us feedback on how we are affecting the atmosphere, or changes from natural
phenomena, such as volcanic eruptions.
In this thesis, a statistical procedure is developed for modelling atmospheric remote sensing
data records, with particular emphasis placed on the ability to extract accurate and
informative information about the long-term trend. Procedures operating on the same principals
have been used in the past for time series analysis in general. For example, on economic
time series, as well as on atmospheric remote sensing data records, or just any atmospheric
data. In this thesis, we show the theory behind the procedure in detail as well as describe
how to implement and use it in practice. This is done with the intent of making the rather
complicated procedure more accessible so that it can become more adopted by scientists
working with atmospheric remote sensing data if desired, and compared to current methods
for obtaining long-term trends.
For an example application of this procedure, we apply it to a stratospheric ozone data
record that extends from 1984 to present (2019). Ozone is a species that is of considerable
interest since we know without a doubt that the changing chlorine situation in the atmosphere
due to human activity has a significant effect on it, and because of its importance in absorbing
ultraviolet radiation, which can seriously harm life on the Earth. The results we give paint
a detailed picture of the long-term trends in stratospheric ozone concentration in the 65ºS
to 65ºN latitude region.
Description
Keywords
Dynamic, Linear, Model, Atmosphere, Time, Series, Trends, Ozone
Citation
Degree
Master of Science (M.Sc.)
Department
Physics and Engineering Physics
Program
Physics