Unfortunately quantifying the groundwater discharge contribution to sea level rise is extremely difficult, suffering from a low
signal to noise problem.
As an addendum, the reason that natural variability is often talked about is because the historical observed record is used to test and constrain the models [and the assumptions that they have made about step 0 and step 3], but the natural variability creates
a signal to noise problem.
Because of
the signal to noise problem, said Seidel, the impacts of solar radiation management can be hard to see.
Not exact matches
Sure, there are differences (I hope) between the pitches I send and the pitches I get, but there's clearly a
signal -
to -
noise problem out there.
That detection was riddled with
problems, drawn out from spurious data, and ignored a low
signal -
to -
noise ratio in search of a sensational new planet, the kind science fiction has long dreamed of.
Obviously there are many confounding factors so the
problem challenge is
to extract the temperature
signal and
to thus distinguish the temperature
signal from the
noise caused by the many confounding factors.
The
problem facing dendroclimatologists is
to extract whatever climatic
signal is available in the tree ring data and
to distinguish this
signal from the background
noise.
Obviously there are many confounding factors so the
problem is
to extract the temperature
signal and
to distinguish the temperature
signal from the
noise caused by the many confounding factors.
There is a
signal -
to -
noise problem evident in climate models which means that, in some mid-latitude regions, predicted climate
signals are too weak.
This is an increasingly pressing
problem for precision radial velocity (RV) spectrographs in the near - infrared (NIR) and optical that require both high stability of the observed line profiles and high
signal to noise.
It's a
signal -
to -
noise problem.
My understanding of most of the (lets call it) skeptical positions from people like Roy Spencer is that they essentially claim exactly that: the absence of a large
signal compared
to noise (or natural variability) and the entire debate is essentially about the question, whether
noise is a measurement / statistical
problem or the very nature of climate itself?
The bottom line is that the identification of human effects on climate is a
signal -
to -
noise problem.
The
problem of differentiating the
signal of intensity from the
noise of frequency remains, and I for one can not think of a research question that could draw from this data an answer
to the «Is AGW causing increases in hurricane losses?»
But while there's a lot of verbiage there, there isn't anything that addresses the basic
problem of attempting
to pretend that there's something significant about a «flattening» that is far more likely
to be
noise than
signal.
Since the late 1970s, it has been recognized that the identification of human effects on climate is inherently a
signal -
to -
noise (S / N)
problem [Hasselmann, 1979; Madden and Ramanathan, 1980; Wigley and Jones, 1981; Wigley and Raper, 1990; Allen et al., 1994; Santer et al., 1994, 1995].
Because that's what the math tells us about the ratio of
signal to noise, just as it would for any
problem containing a
signal -
to -
noise ratio.
The
problem would be that there is no way
to fit the forcing parameters
to aerosols, GHGs, etc, because there is now way
to distinguish internal
noise from external
signal.
I might add that the adjusting, infilling, correcting, kriging etc described by Zeke are superimposed on the basic
problem described by Ms. Gray in her comment
to Watts: We have no intrinsic method of separating
signal and
noise, even given pristine temperature records, and the existing records are anything BUT pristine.
The
problem with this whole approach is that they still have this idea that natural variation is a small «error» ontop of a huge known, and not that natural variation is almost all the
signal of which a small part ought
to be human induced, but you really can't tell because the
noise dominates the
signal.
Obviously there are many confounding factors so the
problem is
to extract the temperature
signal and
to distinguish the temperature
signal from the
noise caused by the many confounding factors.
[DC: There's a
signal to noise ratio
problem at ClimateAudit.
One participant noted that MODIS displays
problems with saturation that could be mitigated for VIIRS by incorporating dual gains especially for the 746 nm channel, and further suggested that
signal -
to -
noise improvements by a factor of two in the 1,240 and 1,610 nm bands would enhance the ocean - sensing capabilities of VIIRS significantly.
The
problem facing dendroclimatologists is
to extract whatever climatic
signal is available in the tree - ring data from the remaining background «
noise».