**The Problem With Modern-Forecasting**
This was originally posted in a weather forum that I am, so please excuse specific references. Thanks. :)
**The Problem With Modern-Forecasting**
I don't know if this is a subject that will interest many of you, but
recently, it has for me. I decided to back and look through my
introductory forecasting books during the past few days, and I found
some really disturbing things that I find lacking in today's
meteorological world. Albeit I am not a professional in the least, and
could barely be considered an amateur forecaster.
One thing
that I find really great about many in this group is that we don't have
consistent "modelology". Most people here are aware that models do not
constitute the completeness of what it means to forecast; in fact, if
anything, models are just guides; not forecasts. The best that a model
can do is SIMULATE how the assumed variables will change through a
specific period of time [and remember, simulations can be FAR from
reality], not forecast. There is a big difference. However, I still feel
as if something is missing.
With the many advances in science
and technology over the past decade or so, society has really begun to
advance at an accelerating rate; however, I believe we are finally
beginning to realize the worst fears of the dystopian sci-fi novels;
progress ISN'T always good. And I believe something similar could be
said of meteorology. Progress in model and computer development has
progressed so much that it has almost removed the human-element from
forecasting. At some NWS offices, they are now being told to go with the
24-hour MOS data instead of questioning it; at other offices,
model-forecasts are taken at face value for medium-range forecasts.
Among many meteorologists, looking at short-range model forecasts for
mesoscale events has replaced real analysis [even though it would be
almost always advisable to ignore any mesoscale-model within 12-hours of
the event, which is the time period in which human-forecast skill
exponentially increases over the short-term model forecast] of
surface-maps and satellite imagery. Essentially, a lot of
modern-meteorology has become an "interpret and regurgitate" mentality;
i.e. "we can't have any possible idea of what the next seven-days will
do, therefore, regurgitate what the medium-range model showed and hope
to apologize when the system changes". I will be the first to admit that
I have done this; and I know many of us have done it on here. But don't
you realize that the human-element is completely gone? Even when we
look at various models and compare various features, and then take a
collective "total" so to speak of each forecast [or decide whether or
not to throw out outliers], do not ensembles already do this? Isn't
there a component of humanity that is needed here? I mean, we are the
only self-aware beings on this planet [as far as we know], and we are
the only organisms in this solar system attempting to understand our
universe, shouldn't the human still be playing the higher part that a
computer doesn't and can't ever play? And that directs me to the article
I was going to post: http://www.flame.org/~cdoswell/forecasting/human_role/future_forecasters.html
I urge anyone interested to read this article, because he first
addresses issues in the NWS itself, and then goes on to critique private
forecasting use of models. He then goes on to argue why human
forecasters will always be essential.
What we are doing now is
not forecasting; whether or not we have individuals who can forecast in
an excellent way [which we do; I know many who can], its something that
is affecting all meteorologists. The surge in technological
capabilities has lead to an even greater reliance on computers in
themselves to do the forecasting for us, and essentially, we leave
without any understanding of what's going on.
This brings up
another article that I wanted to post; a speech by Dr. Len Snellman on
this problem from National Weather Digest in 1991. http://www.nwas.org/members/snellman.php
Of course, I think there are other problems with meteorology today,
including observational limitations, knowledge of our atmosphere,
technology, etc. But I also think that this is a hidden problem that we
sometimes ignore. Not to say that all meteorologists do this [by no
means!], its just that many meteorologists fall into this trap.
What I think is necessary for forecasting is this:
I mean, I think we do have a real problem; because the forecast process
should be sort-of like any scientist. We must apply the scientific
method in a way that is unique to meteorology. I wouldn't even doubt
that using a practical way from mechanics or other field would work.
What is needed, however, is one that is structured to include human
reasoning, cognitive abilities and intuition into the forecast, rather
than just interpreting model-charts and adding some insight every now
and then.
Since the scientific method [in general] begins with
a question, I believe that the forecasting process should begin with a
question of "what is going on". In other words, all forecasts should
begin with analysis. Analyzing includes looking at the atmosphere,
whether through surface observations, satellite-imagery, radar, and even
processed-data fields from super short-range models.
In the
next step of the scientific method, we develop a possible answer to our
problem/solution. This would be analogous to diagnosis in meteorology.
We must first synthesize our analysis into something that can lead to
other questions and/or be a possible explanation for what is going on
through what we observed in the analysis. If we haven't done a
sufficient analysis, we can't do a sufficient diagnosis. We must be able
to explain what we see on the weather-map in terms of our own
experience, knowledge, conceptual models, etc. This will be more
difficult for the amateur with less atmospheric knowledge than the
professional with experience and much more atmospheric knowledge.
In the next-step of the scientific method, a scientist will develop a
test/experiment for the hypothesis. This is essentially a continued step
of what is required of diagnosis in meteorology. We continually monitor
what we are analyzing, and now we synthesize model-output with the
observations to try to develop a coherent picture of what exactly is
going on; since the atmosphere is a continuous fluid and in constant
motion, we only get a brief snapshot of what is going on through our
analysis. That is why diagnosis is necessary, to get the "dT/dt" [change
in the temperature with respect to time] part of analyzing a surface
temperature map or the "dV/dt" [change in the wind vector with respect
to time] part of analyzing surface observations, and thus we can then at
least approximate the change that will occur in a specific period of
time. That is essentially what forecasting is all about; predicting what
"x" is going to be by estimating the current "dx/dt" [with "x" standing
for any scalar variable, or a vector].
This is going to be a
lot harder with longer-range forecasts; especially after the 1-4 day
period. This is when we have to rely upon ensemble and operational model
forecasts for determining what will happen. But that doesn't give us
the right to rely completely on models; that's why we have global
satellite imagery! That's why we have conceptual models and
correlations/experience! I believe that is good to use as well with our
model-data. But like I said, in this period, I think its unavoidable
that we use models if we are planning on forecasting for the 6+ day
time-frame.
Of course, I don't have anything against models,
and I would definitely have to say that without models,
modern-forecasting would not have made near the advances that we have
made. But on the other hand, misuse of model forecasts doesn't make us
better forecasters.
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