Assessing drought recurrence using nonlinear approach
Project background
Currently, in several countries around the world, with the
increase in surface air temperature caused by global warming, erratic and
uncertain rainfall distribution, especially in arid and semi-arid ecosystems is
manifested. Predicting the recurrence of drought cannot be possible without
purposeful investigation of basics of underlying processes. Traditionally,
statistical models have been used for drought forecasting based on linear time
series analysis methods. However, basically linear models assume that the data is
stationary and practically do not enable to deal with non-stationarities and
non-linearities in the related natural processes. Other models and approaches
should be used when non-linearity and non-stationarity play an important role
in forecasting drought recurrence. Based on the above, the main objective of
the proposed research is to investigate features of drought recurrence patterns
at local, spatial and temporal scales, based on available meteorological
variation data sets. This will analyse the non-linear and recurrence properties
of min, max and average air temperature datasets as well as precipitation time
series from different locations in western and eastern Georgia.
Most significant achievements
European Centre on Geodynamical Hazards of High Dams - Georgia :
The project aimed to analyse long time series of
precipitation in 4 countries in order to find retrospectively the
meteorological drought periods (i.e. prolonged period with less than average
precipitation and high temperature) in order to infer the recurrence rate of
droughts. Up to now we have collected long time series of precipitation and
temperature in Georgia for 150 years and from 1988 to 2013 from Algeria. We
intend to calculate The Standard Precipitation Index (SPI) or the Palmer Drought
Severity Index to measure the duration and intensity of the long-term
drought-inducing patterns as well as they persistency/anti-persistency.
Expected results
Expected results year 1
European Centre on Geodynamical Hazards of High Dams - Georgia : Understanding linear/nonlinear properties of meteorological
data sets, especially precipitation and temperature time series for elucidation
of characteristics of drought recurrence
Expected results year 2
New understanding of spatial variation of drought recurrence
in Georgia, Greece, Azerbaijan, Algeria, Turkey and assessing drought
predictive time scales in Georgia, Greece, Azerbaijan, Algeria, Turkey
GHHD
ECMHT
CRSTRA
ECPFE
European Centre on Geodynamical Hazards of High Dams - Georgia
Deliverables year 2
Compilation of a database of electronic time series on
temperature and precipitation from 10 meteorological stations in Georgia for
the last 60 years
Establishing the temporal pattern of droughts in Georgia in
pre-industrial and post-industrial periods using a toolbox of linear/nonlinear
methods
European Centre on Geodynamical Hazards of High Dams - Georgia
Deliverables year 2
Compilation of a database of electronic time series on
temperature and precipitation from 10 meteorological stations in Georgia for
the last 60 years
Establishing the temporal pattern of droughts in Georgia in
pre-industrial and post-industrial periods using a toolbox of linear/nonlinear
methods
Baku office of the European Centre on Training and Information of Local and Regional Authorities and Population in the Field of Natural and Technological Disasters - Azerbaijan
Deliverables year 2
Centre for Scientific and Technical Research on Arid Regions Omar El Bernaoui - Algeria
Deliverables year 2
European Centre on Prevention and Forecasting of Earthquakes - Greece
Deliverables year 2
Collection of time series of 118 years of required data (max
temperature, precipitation) for Athens and relevant time series from 5-10
stations spread in Greece since the 50s