A comparison
of the linear trends from these two series indicates that about 69 % of the increase in ocean heat content during 1955 to 1998 (the period when estimates from both time series are available) occurred in the upper 700 m of the World Ocean.
The continuation
of the linear trend from August 1975 to July 1997 (green dashed), would have predicted a temperature anomaly in August 2012 of 0.524 ºC.
A comparison
of the linear trends from these two series indicates that about 69 % of the increase in ocean heat content during 1955 to 1998 (the period when estimates from both time series are available) occurred in the upper 700 m of the World Ocean.
Not exact matches
The number
of stair - related injuries decreased 11.6 % during the study period, with a significant
linear trend from 101335 cases in 1999 to 89619 cases in 2008 (m = − 1103, P =.011).
(Bottom) Patterns
of linear global temperature
trends from 1979 to 2005 estimated at the surface (left), and for the troposphere (right)
from the surface to about 10 km altitude,
from satellite records.
The increases in frequency and duration metrics translate to 30 additional marine heatwave days per year by the end
of the 35 - year period (p < 0.01; based on a
linear trend)
from a baseline level
of about 25 days in the 1980s (Fig. 2).
Because
of the stratospheric warming episodes following major volcanic eruptions, the
trends are far
from being
linear.
The
trend is not
linear, and the warming
from the first 50 years
of instrumental record (1850 — 1899) to the last 5 years (2001 — 2005) is 0.76 °C ± 0.19 °C.
Figure 2: The data (green) are the average
of the NASA GISS, NOAA NCDC, and HadCRUT4 monthly global surface temperature anomaly datasets
from January 1970 through November 2012, with
linear trends for the short time periods Jan 1970 to Oct 1977, Apr 1977 to Dec 1986, Sep 1987 to Nov 1996, Jun 1997 to Dec 2002, and Nov 2002 to Nov 2012 (blue), and also showing the far more reliable
linear trend for the full time period (red).
They fail to mention it also removes any
linear trend, which is obvious
from just a few steps
of basic arithmetic.
Figure 5.5 shows the
linear trends (based on pentadal anomaly fields)
of zonally averaged salinity in the upper 500 m
of the World Ocean and individual ocean basins (Boyer et al., 2005)
from 1955 to 1998.
While using a percent growth rate for free cash flows might be conventional, mathematically convenient and easier to convey to others, it is not as accurate or conservative as using an absolute rate
of change
from a
linear trend model.
But even though Call
of Duty: WWII continues the typical
trend of linear heroic storytelling mixed with incredible and explosive action set - pieces, there are a few small changes that makes the whole experience differ slightly
from previous campaigns.
The standard deviation
of the residuals
from a
linear regression to annual averages 1975 - 2007 is 0.472, so we expect a range
of variation
of roughly + / - 0.94 deg.C
from the long - term
trend.
BPL: A
trend is present if the
linear regression
of a time series against elapsed time is significantly different
from zero.
It is arguably impossible to accurately detangle a multidecadal oscillation
from a long - term (probably not
linear) forced
trend in 100 years
of data.
As a result
of this evaluation our conservative estimates
of the uncertainty
of the
linear ice volume
trend from 1979 - present is about 30 %.
[Response: At the time (1988), there were no suggestions that climate should be following a
linear trend (though if you know
of some prediction along those lines
from the 1980s, please let me know — the earliest I can find is
from 1992, and the prediction was for 0.1 degC / dec).
One baseline model is a simple
linear trend from the start
of the century.
The DSLPA index computed
from HadSLP2 shows a much more «
trend - like» reduction than the datasets shown in the manuscript, in which the 1970s shift plays a less pivotal role; though the amplitude
of slope
of the
linear trend is consistent with the model and observations.
Internal variability as estimated
from observations can't explain sea - ice loss Superposition
of a
linear trend and internal variability explains sea - ice loss Observational sea - ice record shows no signs
of self - acceleration
I think it's just another way
of saying that the volume series has an accelerating downward
trend, while the other measures (extent, area) are not easily distinguishable
from a
linear trend — at least over the (unspecified) period you're using.
I went to the trouble
of fitting a
linear trend line to the A2 model input line
from 2002 - 2009 and obtained a correlation coefficient (R2)
of 0.99967.
Pielke apparently did not understand why the temperatures before 1910 hardly affect this conclusion (in fact increasing the probability
from 78 % to 80 %), and that the
linear trend from 1880 or 1910 is not a useful predictor for this probability
of breaking a record.
Also, about 2/3
of the individual ensemble - members (46 out
of 68)
from all the model runs have
linear trends that indicate at least a nominal weakening — this is significantly different
from what one would be expected
from a Binomial distribution with a 50 % probability.
# 242 Jim Eager in # 229 showed graphs
of the
linear trend of monthly data
from January 1999 through December 2008.
To conclude, a projection
from 1981 for rising temperatures in a major science journal, at a time that the temperature rise was not yet obvious in the observations, has been found to agree well with the observations since then, underestimating the observed
trend by about 30 %, and easily beating naive predictions
of no - change or a
linear continuation
of trends.
Piece-wise joined or step - like constructs
of linear trends (figs 1 and 3) would always suffer
from the arbitrariness
of the breakpoints.
Of course, as they point out «because rainfall is such a variable element, trend values are highly dependent on the start and end dates of the analysis» and the fact they are simply using linear interpolation it is very difficult to derive anything meaningful in terms of climate change from just one ma
Of course, as they point out «because rainfall is such a variable element,
trend values are highly dependent on the start and end dates
of the analysis» and the fact they are simply using linear interpolation it is very difficult to derive anything meaningful in terms of climate change from just one ma
of the analysis» and the fact they are simply using
linear interpolation it is very difficult to derive anything meaningful in terms
of climate change from just one ma
of climate change
from just one map.
In «The Evolution
of ENSO and Global Atmospheric Temperatures», Trenberth et al identify the
linear trend in global temperatures that result
from ENSO events: «For 1950 - 98, ENSO linearly accounts for 0.06 deg C
of global warming.»
12 - month running averages are shown as well as
linear trend lines, and compared to the scenarios
of the IPCC (blue range and lines
from the 2001 report, green
from the 2007 report).
Note the sizeable departure
of the data
from the
linear - plus - cyclic
trend over the last several decades.
Our reconstruction
of his prediction takes the natural variability
of ENSO, the sun, and volcanic eruptions
from Foster and Rahmstorf (2011)(with a 12 - month running average) and adds a 0.02 °C per decade
linear warming
trend.
You downplay the fact that «homogenization»
of the Hobart RO record has increased the fitted
linear trend from 1893 - 1992 by a factor
of ~ 1.6 by appealing to mysterious «confidence intervals.»
It's stated in the text, but understanding that the absolute deviation
of the Earth's LOD
from its long — term
trend refers to the absolute value
of the deviation
from a
linear trend fit, whatever the sign
of the deviation.
Eg (
from Georgia Tech blurb): «The
linear trend was removed
from all indices to focus only the multi-decadal component
of natural variability.»
The
linear trend of global mean SLR
from 2004 to 2015 amounts to 3.38 ± 0.10 millimeters per year, and the σ
of the detrended global mean is 3.90 millimeters (Table 1).
The «noise level,» that is, the amplitude
of internal variability, approximated here by the standard deviation (σ)
of the OHC time series after the
linear trend is removed, amounts to 0.77 × 1022 J
from 2004 to 2015 (Table 1).
Figure 2: The data (green) are the average
of the NASA GISS, NOAA NCDC, and HadCRUT4 monthly global surface temperature anomaly datasets
from January 1970 through November 2012, with
linear trends for the short time periods Jan 1970 to Oct 1977, Apr 1977 to Dec 1986, Sep 1987 to Nov 1996, Jun 1997 to Dec 2002, and Nov 2002 to Nov 2012 (blue), and also showing the far more reliable
linear trend for the full time period (red).
So perhaps Mr. House can try to learn a little science rather than expatiating with malevolent ignorance on everything
from the least - squares
linear - regression
trend on monthly temperature anomaly datasets to the arcana
of United Kingdom peerage law.
And that is not going to happen any time soon even if you take the totally unjustified and unscientific step
of fitting a
linear «
trend» to 35 years
of data taken
from a system with a sizeable 60y periodicity and project it 85 years into the future.
These are included in the HadCRUT4 ensemble, and when computing
linear trends in global temperatures
from August 1997 to August 2012 these give a
trend of 0.034 ± 0.011 °C per decade (95 % confidence interval) for the observed portion
of the earth.»
Guest post by Clive Best The UK Met Office seem determined to stand by their claim made in response to the David Rose article in the Mail on Sunday: «The
linear trend from August 1997 (in the middle
of an exceptionally strong...
the totally unjustified and unscientific step
of fitting a
linear «
trend» to 35 years
of data taken
from a system with a sizeable 60y periodicity and project it 85 years into the future.
Muller et al., 2011 found that the
linear trends of the Unadjusted records for stations with Ratings 1, 2 or 3 were comparable to those
of stations with Ratings 4 or 5, and that there was not much difference between estimates constructed
from the Ratings 1 - 3 and Ratings 4 - 5 subsets
of the USHCN.
Chart # 1 had 1919 - 1943 anomaly plot adjusted to start at same anomaly point as 1991 - 2015 period; chart # 2
linear trends are based off plots
of chart # 1; chart # 3 uses 5 - year averages calculated
from each period's anomaly dataset and then the 1919 - 1943 5 yr average was adjusted (i.e. offset) to start at same anomaly point as 1991 - 2015 5 yr average; chart # 4 cumulative differences calculation: the December 31, 1943 anomaly minus the December 31, 1918 anomaly and the December 31, 2015 anomaly minus the December 31, 1990 anomaly (both calculations covering a full 300 months).
If the DATA were falling off that extension
of the
linear trend line
from 1975 to 1997, then that might be evidence that the warming was really slowing down.
The data is annual data
from 1955 to 1995, with a mean
of 23.025 C, a Standard Deviation
of 0.2981 C, and a
trend of 0.05 + / - 0.08 C / 10 years, as determined by simple
linear regression.
http://www.skepticalscience.com/graphics.php?g=47 The data (green) are the average
of the NASA GISS, NOAA NCDC, and HadCRUT4 monthly global surface temperature anomaly datasets
from January 1970 through November 2012, with
linear trends for the short time periods Jan 1970 to Oct 1977, Apr 1977 to Dec 1986, Sep 1987 to Nov 1996, Jun 1997 to Dec 2002, and Nov 2002 to Nov 2012 (blue), and also showing the far more reliable
linear trend for the full time period (red
1) A 0.2 °C per decade global warming
trend 2) Two «natural cycles» (cosine functions) both with 0.15 °C amplitude and periods
of 10 and 20 years, respectively 3) Random noise with 0.07 °C amplitude 4) The sum
of the warming
trend, cycles, and noise 5) The sum fit with a step function with three steps:
linear trends from 1950 to 1963, 1967 to 1986, and 1987 to 2003 (light blue) 6) The sum with a
linear trend fit
from 1950 to 2010.