jungle

NCDC Frequently Asked Questions


Can the observed changes be explained by natural variability, including changes in solar output?
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Since our entire climate system is fundamentally driven by energy from the sun, it stands to reason that if the sun's energy output were to change, then so would the climate. Since the advent of space-borne measurements in the late 1970s, solar output has indeed been shown to vary. With now 28 years of reliable satellite observations there is confirmation of earlier suggestions of an 11 (and 22) year cycle of irradiance related to sunspots but no longer term trend in these data. Based on paleoclimatic (proxy) reconstructions of solar irradiance there is suggestion of a trend of about +0.12 W/m2 since 1750 which is about half of the estimate given in the last IPCC report in 2001. There is though, a great deal of uncertainty in estimates of solar irradiance beyond what can be measured by satellites, and still the contribution of direct solar irradiance forcing is small compared to the greenhouse gas component. However, our understanding of the indirect effects of changes in solar output and feedbacks in the climate system is minimal. There is much need to refine our understanding of key natural forcing mechanisms of the climate, including solar irradiance changes, in order to reduce uncertainty in our projections of future climate change.

In addition to changes in energy from the sun itself, the Earth's position and orientation relative to the sun (our orbit) also varies slightly, thereby bringing us closer and further away from the sun in predictable cycles (called Milankovitch cycles). Variations in these cycles are believed to be the cause of Earth's ice-ages (glacials). Particularly important for the development of glacials is the radiation receipt at high northern latitudes. Diminishing radiation at these latitudes during the summer months would have enabled winter snow and ice cover to persist throughout the year, eventually leading to a permanent snow- or icepack. While Milankovitch cycles have tremendous value as a theory to explain ice-ages and long-term changes in the climate, they are unlikely to have very much impact on the decade-century timescale. Over several centuries, it may be possible to observe the effect of these orbital parameters, however for the prediction of climate change in the 21st century, these changes will be far less important than radiative forcing from greenhouse gases.


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NOAA recently hedged their bet as to causation.
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http://www.dailymail.co.uk/sciencete...#ixzz1krX3weLa


Forget global warming - it's Cycle 25 we need to worry about (and if NASA scientists are right the Thames will be freezing over again)Met Office releases new figures which show no warming in 15 years
By David Rose
UPDATED: 00:38 EST, 29 January 2012
Comments (702) Share

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The supposed ‘consensus’ on man-made global warming is facing an inconvenient challenge after the release of new temperature data showing the planet has not warmed for the past 15 years.
The figures suggest that we could even be heading for a mini ice age to rival the 70-year temperature drop that saw frost fairs held on the Thames in the 17th Century.
Based on readings from more than 30,000 measuring stations, the data was issued last week without fanfare by the Met Office and the University of East Anglia Climatic Research Unit. It confirms that the rising trend in world temperatures ended in 1997.

A painting, dated 1684, by Abraham Hondius depicts one of many frost fairs on the River Thames during the mini ice age
Meanwhile, leading climate scientists yesterday told The Mail on Sunday that, after emitting unusually high levels of energy throughout the 20th Century, the sun is now heading towards a ‘grand minimum’ in its output, threatening cold summers, bitter winters and a shortening of the season available for growing food.
Solar output goes through 11-year cycles, with high numbers of sunspots seen at their peak.
We are now at what should be the peak of what scientists call ‘Cycle 24’ – which is why last week’s solar storm resulted in sightings of the aurora borealis further south than usual. But sunspot numbers are running at less than half those seen during cycle peaks in the 20th Century.
Analysis by experts at NASA and the University of Arizona – derived from magnetic-field measurements 120,000 miles beneath the sun’s surface – suggest that Cycle 25, whose peak is due in 2022, will be a great deal weaker still.



Read more: http://www.dailymail.co.uk/sciencete...#ixzz1yAcF2DfC

todd1200

Okay great, then we agree.

FDXLAG

You do realize your chart had a 1.3 degree change over 130 years. Show me the chart for the period 1280 to 1410. Then we will talk.

jungle

Not really, NASA, NOAA and many other researchers are spending more on solar research. The purely CO2 driven models have been an abject failure in climate prediction.

It is clear man had nothing to do with most of the climate change in history, and as of yet there is no clear division between man made warming and cosmic effects. Lots of speculation and theory, but no real link, and no real proof.

This suggests the whole problem is much more complex than first thought.

DYNASTY HVY

Are you trying to say that all this drama and hair pulling is over a few degrees during a given time period ?
I still say that a total revamp in EDUCATION is the key ,any thoughts as to how this schould be done?




Ally

todd1200

Of course the problem is complex and many factors effect the earth's climate, but what you summarized as "NOAA hedging their bets as to causation" was actually the opposite -- if you read what you posted, you'll realize that NOAA was refuting alternate theories and stating that variations in solar energy are inadequate to explain the historically unprecedented rise in global surface temperatures. If you happen to consider NOAA a valid source of information here is a link to more of their findings --
Global Climate Change Indicators

todd1200

Since direct temperature measurements are available only from the nineteenth century onward (and even then, only recorded broadly in the northern hemisphere) historical charts depend on statistical models, and as such are subject to manipulation. Here's a chart that includes a number of models, but I'm sure you can find one eliminates all but the Bauer model --

jungle

Those are pretty charts.

Can you tell us what part of climate change is natural and what part is caused by man?

You know, causation, correlation, all that sort of thing.

Can you tell us exactly how NOAA has proven the sun has no short term effect?

What caused the massive climate changes prior to man?

Why do you think this happened:Based on readings from more than 30,000 measuring stations, the data was issued last week without fanfare by the Met Office and the University of East Anglia Climatic Research Unit. It confirms that the rising trend in world temperatures ended in 1997.

todd1200

Now that you've realized that the findings of NOAA actually run counter to your ideology, I'm not surprised that they've become instantly discredited in your eyes. You're free to disregard the opinion of every single nationally or internationally accredited scientific research organization in the world. You can also question the number of hydrogen atoms in a molecule of water, the diameter of Jupiter, or the amount of potassium in a banana -- but to pretend that you're being motivated by anything other than political ideology is disingenuous. Would Watts be such a trusted source of information if his findings did not support your ideology?

If a man weighs 500lbs., exactly how many pounds are due to lifestyle choices and exactly how many pounds are due to genetic predisposition? How much would he weigh if he had a different set of genes? Even if you can't answer those questions, it is clear that he would be better off if he went on a diet and started to exercise.

jungle

Again, you seem dead set on political ideology and refuse to even consider science-except that science which serves your ideology.

We don't have all the answers and to think that the science is never going to change plays right into ideology.

Consider this, if the Earth cools or warms what real difference is there if some of it is caused by man or not, what exactly are you going to do about it? How exactly would that alter the effects?
Do you actually believe that mankind will suddenly stop using carbon fuels, do you actually think we can really just supply all of our energy needs by some unstated and unproven methods?

Can you give us some idea of the economic impact this would have?

Clearly a great deal of disagreement still exists, both in the data sets and in the theory.
Why do you think this happened:Based on readings from more than 30,000 measuring stations, the data was issued last week without fanfare by the Met Office and the University of East Anglia Climatic Research Unit. It confirms that the rising trend in world temperatures ended in 1997.

Again, I must ask, what caused all of the climate change prior to human existence?

It is common to think ideology plays some role in the views of science, but tell us which ideology is correct. How could ideology ever really effect science? Let us know when we have all the answers, let us know when science is static.

Lastly sir, you mistake me for someone of a particular ideology, nothing could be further from the truth. Ideology and governments have killled more people in the last century than anything except disease. All ideology when viewed in the light of reality is little more than one group of humans trying to control another. You don't want to be a part of that do you?