Climate: Round I

When you base political and financial gains off a hot topic issue, you start losing credibility in my book.  Headlines that read climategate, regardless of what the actually e-mails said, don't bode well for your stance.

Climate changes are cyclical.  They have been since day one and will be forever.  Where you are sitting now at one time was covered by water and ice for thousands of years.  It experienced extreme drought and bone chilling cold.  That's all part of the cycle through millions of years of warmth and cold.

What first made me what I guess you'd say a skeptic was that initially when the global warming trend started, proponents told of endless summers, droughts, snowless winters and after the 2005 hurricane season, stronger and more dangerous tropical storms.  When the patterns didn't produce what they had said, they simply changed their definition that basically said global warming causes all kinds of strange weather.  And let's call it climate change, not global warming.  In an essence, these changes can include increased flooding, drought, extreme heat, unusual cold, warm winters, cool summers, excessive snowfall, windier winds, wetter dryness and a case of the runs.  If every type of weather somehow proves the existence of climate change, I once again question the credibility.

If you look at the history of temperatures, you would notice a similar wave-like trend.  They go up slowly, peak, and come down slowly before hitting a bottom and the pattern continues.  Now what we often hear is how a particular year ranked in the historical records of warmth.  I'm not going to deny that lately, many years have been near the top.  But forgive me if I'm not blown away.  Historical records?  I guess if you want to consider the mid to late 1800's historical.  Basically we are comparing let's say the last 150 years worth of global temperatures.  That is an extremely minute period of time and data to label as record breaking.  And this is neither the warmest or fastest changing warmth the planet has ever seen. 

I follow the cycles.  The big news story in 2007 was that the ice had melted so much that the northwest passage above Alaska and Canada was open.  Many outlets reported that this was the first time this had ever occurred (if ever dated back to 1978).  See, that is when satellite images started being used to monitor sea ice.  The passage actually was opened during the 1920's and in 1939 and 1940.  That was when we were in one of those "bizarre" warming phases when global warming was going nuts.  

To the right is an entire section of the Pittsburgh Press dated from December of 1922.  

The headline reads, "Strange Things Happening in the Frozen Arctic."  It goes on to talk about how fast the ice is melting and the change on animals and humans.  

The cause of it all: Unknown

Here is the header before the article.  Any of this sound familiar?

And this is from 1922.

They do mention any interesting topic.  The warming of the polar sea.

There has to be some sort of reasonable explanation as to why virtually the same thing happening now (or more accurately four to five years ago) also happened in the 1920's, 30's and 40's.  After all, I wasn't around but I don't think many people heard about climate change in the 60's or 70's.  You once again have to go looking for those patterns, and the Pacific Decadal Oscillation is just the place to start.

The PDO is a climate index based off of sea surface temperature in the North Pacific.  There are two phases, a positive phase that warms the Northern Hemisphere and a negative phase that cools it.  These phases tend to last roughly 30 years before switching over.  Think of this pattern as a much longer lasting El Nino (warm equatorial waters) and La Nina (cool equatorial waters) except the warm or cool waters are in the northern pacific.  Here is a map that shows the phases.

  
By the way, this is taken right off an NOAA website and not some unscientific source.  I don't really think it is hard to see a pattern here.  The warm period according to observers of this pattern began, for the purpose of this map, begins in 1924.  Let's break it down, 1920's through the 1940's saw a positive phase and thus a warmer period.  The late 1940's to the late 1970's had the PDO in a negative phase.  From the late 70's to around 2000 it turned back to a warm phase.  It has since bounced a bit, but most agree that it would seem likely it is returning to a cooler phase.  Now do the math and add the time periods up.  You get roughly a 30 year pattern.  And had the map been extended further, the cool PDO period prior to 1924 would have started in 1890.

Here you can see how these phases, in reaction to the weather patterns in the southern pacific, effect the weather in North America primarily in the winter.  And if you remember awhile ago when I talked about snowfall totals in Allentown, 9 of the top 11 snowiest winters since 1922 have occurred in a cool PDO phase.


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Now I already know what you are saying.  You give a mention to the sibling Nino's, and this PDO (that quite frankly I've never heard of before) but what about the Atlantic ocean and the craziness that goes on in the arctic?  I'm glad you asked.  In to the conversation comes the North Atlantic Oscillation or NAO for short.

Again this type of pattern comes in two phases and effects eastern North America, and more specifically the northeast part of the United States along with western and central Europe.  Changes to temperature, jet stream, storm track and intensity of winter storms all come into play with this setup.  Positive NAO for us generally means an increase in temperature or in clearer terms, a lack of punishing winter storms.  A negative NAO is just the opposite.  Storms ride up the coast, cold air is trapped and storms hit hard.  Every winter season has periods of positive NAO followed by negative turns. 

With more calculations than I ever could explain, here is the current NAO forecast.  Simply put, the time frame around March 20-22 is clearly a time to watch.  This is a very typical NAO map.

When forecasters see that dip, that is when they start talking storms.  I have to be careful not to confuse PDO with NAO.  A positive NAO phase does not mean it will be necessarily "warmer", it merely shows when things could become interesting, i.e. Nor'easter.  However like the PDO phases that last decades, winter NAO phases also have a tendency to be more pronounced for longer periods of time before they shift.

For this next part I will be taking the exact phrases off the NOAA's Climate Prediction Center that discusses positive and negative phases of the NAO over the course of a year.  

The negative phase of the NAO dominated the circulation from the mid-1950's through the 1978/79 winter. During this approximately 24-year interval, there were four prominent periods of at least three years each in which the negative phase was dominant and the positive phase was notably absent.

An abrupt transition to recurring positive phases of the NAO then occurred during the 1979/80 winter, with the atmosphere remaining locked into this mode through the 1994/95 winter season. During this 15-year interval, a substantial negative phase of the pattern appeared only twice

It goes on to say how documented conditions have shown a turn back towards a negative phase in the NAO. So just for a quick run down, the NAO went through a negative phase from the mid 50's to late 1970's before an abrupt positive transition took place until the mid 1990's.  Now let me refresh the memory about the PDO phases.  Heck, even scroll back up and look at the PDO map.   

From the NOAA on PDO:

Warm and cold phases can persist for decades.  For example, a warm phase continued from 1925 to 1946 and a cool phase from 1947 to 1976.  From 1977 to 1998, another 21–year warm phase occurred.  Recently, however, these decadal cycles have broken down.

Compare the two.  PDO was in a warm phase from the 20's to the 40's that saw warmer ocean temperatures in the North Pacific causing a general warming period.  PDO shifted in 1947 to cool phase until 1977.  NAO data went negative from the mid 50's until 1978-79 which both resulted in cooler temperatures.  PDO shifted back after 1977 through 1998 to a warm phase and incredibly the NAO went abruptly positive in 1979-80 to 1995.  PDO cycles started breaking down in 1998.  Hard to believe the NAO had a similar break down in 1997. 


Golly, it's almost like everything is tied together.  The North Pacific patterns effect the North Atlantic pattern that directs weather based from Pacific equatorial patterns.

Cycles, patterns, variation.  This is climate.