location method and to map the faults that they occur on. Due to the
high clock-accuracy of the Icelandic SIL seismic network, the method can, through cross-
correlation, reduce the uncertainties in relative arrival times and thus increase relative
location accuracy to as far as tens of meters. This enables fault mapping by grouping
together relocated events that form apparent lineaments
/media/vedurstofan/utgafa/skyrslur/2010/2010_003rs.pdf
(Dowdeswell et al., 1997; Björnsson and Pálsson, 2008; Cubasch et al. 2013; Agústsson et
al., 2015).
General Circulation Models (GCMs) simulate climate changes on a large spatial scales. They
can be downscaled in several ways to study climate in more details. When this is done
statistically, a correlation is found between observations and results from GCMs modelling
of the past
/media/vedurstofan-utgafa-2017/VI_2017_009.pdf
(e.g. Gaussian; second-order
stationarity; degree of temporal and spatial autocorrelation).
Furthermore, correlation in time and space is characterised
by correlogram/variogram functions. Categorical data (3) dif-
fer from numerical data (1, 2), because the categories are not
measured on a numerical scale.
A software tool, the data uncertainty engine (DUE), for
supporting the assessment of data
/media/loftslag/Refsgaard_etal-2007-Uncertainty-EMS.pdf
but for precipitation changes.
Changes in local temperature are strongly controlled by the large-scale temperature change.
This is reflected both by the small amplitude of the regression residuals (typically 0.1-0.3°C)
and the large explained variance (mostly above 80%, with some exceptions like the Baltic
Sea). For changes in precipitation, the correlation between the local and the large-scale
changes
/media/ces/D2.3_CES_Prob_fcsts_GCMs_and_RCMs.pdf
model
Somewhat
plausible
Competing
schools
1 Weak
correlation but
commonalties
in measure
Educated guesses
indirect approx. rule
of thumb estimate
Preliminary theory Grey box model Not very
plausible
Embryonic
field
0 Not correlated
and not clearly
related
Crude speculation Crude speculation Black box model Not at all
plausible
No opinion
Example from Refsgaard et al
/media/loftslag/Refsgaard_2-uncertainty.pdf
), with the intention of
illustrating the relationship between temperature and nature of trends in snow parameters. To
further investigate snow parameters‟ sensitivity to variations in winter climate, we performed
an analysis of correlation with time series of mean winter temperature and accumulated winter
precipitation.
Results show a transition from more and more negative trends in number
/media/ces/ces-oslo2010_proceedings.pdf
to a subset of near-by events from the
event library via cross-correlation of P and S waveforms. The relative times are inverted for
best location, resulting in a high-precision automatic location for the new event available
within minutes. As more waveforms arrive, the process is repeated to improve the location.
The location accuracy that can be achieved is from tens of meters to a few hundred meters
/media/vedurstofan/utgafa/skyrslur/2010/2010_012rs.pdf
Recorded seismicity by the SIL-system in Eyjafjallajökull and nearest
vicinity between 1991 and August 2006.
3.2 Method
We used a multi-event, double-difference relocation method to relocate the earthquakes
(Slunga et al., 1995). The method uses cross-correlation of similar wave forms to
determine relative travel times of waves from events to stations with increased accuracy.
This can
/media/vedurstofan/utgafa/skyrslur/2009/VI_2009_013.pdf
difference in averages
alone. This amounts to minimising local normalised mean squared deviations, without changing
the correlation between modelled and measured time-series. However, the linear transformation is
only applicable to mean fields, with a sufficiently long averaging period, to allow for representative
averages and standard deviations to be calculated. An application of the linear
/media/vedurstofan/utgafa/skyrslur/2013/2013_001_Nawri_et_al.pdf
fields); automated feature tracking (using the VISICORR software
(Dowdeswell and Benham, 2003)); and a semi-automated Fourier-transform based cross-
correlation technique. In this paper, we extend this analysis to investigate the impact of
various pre-processing steps (such as slope shading of the surface derived from the point
cloud); the impact of the window size used to calculate the Fourier
/media/vatnafar/joklar/Reykholt-abstracts.pdf