Thursday, August 13, 2015

Some Notes Meteorological & Astronomical -OR- On Midday Suburban Office Park and Late Night Urban Apartment Views Of and To Nowhere

The Sun briefly veiled behind a fair-weather cumulus cloud over the strange structure of the Metroplex building located just off Rt. 50 in Landover, Md., 10:56AM August 12, 2015.

I had to go to our office in this building today. I rarely go there (perhaps once or twice a year).

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A(nother) late night blog posting following an OK work day -- except the morning Metro ride featured the obligatory problems (this time, a track signal issue) that delayed me a half hour -- and a gym visit. I just made dinner and now I'm posting this entry way too late.

As for the entry, I'm going to try to post it but my internet connection keeps going in and out. Furthermore, I only have my work computer at home (with its problematic internet traffic routing through the Barracuda security).

A swampy area created by what I think is the Beaverdam Creek (at least that's the name on the map) along Corporate Drive next to the New Carrollton Metro, Landover, Md., 10:51AM August 12, 2015.

This is a strange and isolate spot -- a suburban no man's land purgatory -- hemmed in by Rt. 50 and the nearby Capital Beltway and all the looping interchanges and exits between them and other roads. I was walking from the Metro (after the typical delayed ride) to the Metroplex building.

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This is because my new used home computer that Andrea kindly gave me for free -- it's an ASUS Notebook with a Windows 7 operating system -- is being kindly thoroughly updated by Andrea with the whole Microsoft Office suite and a more up-to-date Internet Explorer and other stuff.

However, the computer is at work where this is being done, and -- as I noted in my previous entry and some of the pictures in this entry attest -- I was not in my regular office today but in the Landover office near the New Carrollton Metro, so I could not retrieve it.

The view from one of the upper floors of the Metroplex building, Landover, Md., 1:03PM August 12, 2015.

I think this is looking northwest. Looking to the southwest, you cannot see the tip of the Washington Monument (at least from this floor) because some low hills are in the way. However, you can see the Hughes Memorial Tower.

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The weather this Wednesday was -- as I mentioned in my previous entry -- a very sunny one with highs in the 80s Fahrenheit (it reached 85F at KDCA) with afternoon dew points around 55F. Tonight is clear and pleasant (i.e., not oppressive and digustingly humid) with temps. at the midnight hour ranging from 66F to 74F (the highest being at KDCA).

I should point out (and the pictures directly above and below attest to the fact) that despite what I said about no clouds, there were actually beautiful puffy cumulus clouds filling the early afternoon clean blue sky, although they dissipated by early evening.

The view from the Metroplex building looking to the west over Prince George's County, 1:03PM August 12, 2015.

The nearby buildings (on the other side of the Metro station and train tracks) is an IRS complex in what I think is Lanham. (The place names are a bit fuzzy in this part of Prince George's County.)

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Speaking of the Reagan Washington National Airport climate (weather observation) station (that is, KDCA), the NWS took the unusual step of replacing the thermometer -- er, temperature sensor -- that has been in use there after a spate of critical news stories noting how unusually warm the readings were there not just this summer with the suspiciously high number of 90F+ days compared to the rest of the region, but also in the past year.

Heat waves distort the images of jets on the tarmac at Reagan Washington National Airport; photo by Jim Lo Scalzo, European Pressphoto Agency, date uncertain.

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Things really got going with this Capital Weather Gang entry on Aug. 5th (link embedded): Is D.C.’s weather station reading way too hot?

The CWG (Jason Samenow, that is) noted the temperature sensor change in this Aug. 11th, 2015 entry (link embedded): Weather Service replaces ‘too high’ temperature sensor at Reagan National Airport.

A map through Aug. 3, 2015 of the number of days with high temperatures of at least 90F across a large portion of the eastern half of the U.S. including the mid-Atlantic, Southeast, Appalachians, Ohio River Valley, and Midwest.

The stations show here are all WBAN ones (i.e., those with Weather Bureau-Army-Navy numbers) including a subset -- such as KDCA, KBWI, and KIAD in our region -- that are the long-term climatology stations.

This map was included in the August 3rd and August 11th entries.

Through Aug. 3rd, KDCA was at 36 days (tying the current normal full seasonal average* with well over a month to go during which temps. can easily reach 90F or better).

By contrast, the other main regional climate stations featured 16 at KBWI; 22 at KDMH (the Maryland Science Center); and just 10 at KIAD at just 10. (KDCA as of Aug. 13th is at 39 days.)

*To be clear, the highest average temp at KDCA is 89F running from July 7th - July 22nd, inclusive, in the current 1981 - 2010 base period, but there are still an "average" number of days with temps of at least 90F for highs, and that tally is 36.

I'd be happy if the NWS would just move the damn "official" Washington, D.C., climate station elsewhere -- ideally, the U.S. Naval Observatory or maybe somewhere in Georgetown.

An old structure -- a signal tower, I believe -- located along the Amtrak / MARC Penn Line near the New Carrollton Metro station, 10:41AM August 12, 2015.

This is visible from the Metrorail line, which runs parallel to the tracks at that point. I've featured this structure in at least one other entry back in July 2012. (The graffiti on it really hasn't changed!)

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Continuing with the weather theme, more specifically, the long-term outlook for the winter, I meant to mention that the GMAO coupled model has produced quite a "forecast" that shows another cold and potentially snowy U.S. East Coast winter.

Below are three images that Gary -- who works for the GMAO and the Goddard Space Flight Center -- sent me these images the other day. They include my explanations.

In short, I believe this particular model prediction -- for the 90-day period including December 2015, January 2016, and February 2016 (denoted "2015DJF") -- is the result of combination of the current major warm ENSO event, the warm phase PDO, and a negative Arctic Oscillation (AO) with the wintertime polar vortex once again "knocked off" the North Pole and out of the Arctic and into the mid-latitudes of the "Western" (rather than "Eastern") Hemisphere (although there seems to be a lobe of the polar vortex over the North Pacific).

The 500 millibar height anomalies initialized in August 2015 predicated for 2015DJF period (as defined). Anomalies are in dekameters.

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The 2-meter temperature anomalies for North America forecasted for the 2015DJF period.

The brownish areas over Alaska and the Yukon Territory represent +4C anomalies for the full 90-day period, which is tremendous and continues the pattern of scary global climate change-induced warming in evidence in the Arctic and sub-Arctic. The violet shading over the Ohio and lower Mississippi River valleys are -3 to -4C anomalies for the same period.

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The forecasted precipitation rate anomaly in millimeters per day for North America for the 2015DJF period.

Between the temperature and precipitation anomalies, if this verified, it would be a cold and wet (snowy?) winter for the mid-Atlantic region.

The really good news is that if this verified (a big IF), California would finally get a significant amount of desperately needed rainfall and mountain snows. However, it shows once again absurdly warm temperatures for Alaska and much of northern Canada.

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The Perseid Meteor Shower: A Few Thoughts

Image from the 2007 Perseids meteor shower which was one of the more intense Perseids events in recent memory. (NASA). Source here.

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Tonight is the peak of the annual Perseid meteor shower -- created as Earth passes through the dust tail left by the Comet Swift–Tuttle, which orbits the Sun every 133 years and -- beyond the next 2,400 years is actually something of a potential threat to Earth.

Caption: A near-Earth perspective of its orbit, the radiant of the Perseid meteor shower, and the orbit of the shower’s parent comet, 109P/Swift-Tuttle, to show their spatial relationships on August 12 00:00 UTC. The Perseid debris cloud is fairly wide (~0.1 AU), filling the frame.

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I mention this because, as always seems to be the case with these annual meteor showers (in particular, the Perseid and the Leonid), there is a spate of stories such as this one declaring how it will be truly spectacular. (Yes, in some years such as 2007, it was.) As usual, I saw nothing tonight from my ridiculous vantage point in "midtown" Washington, D.C., during my brief time outside as I walked back from the gym.

Caption: An illustration from the 1872 Popular Science Monthly showing the intersection of Earth’s orbit with the orbital path of Comet Swift-Tuttle (Perseid meteoroid stream). Bits and pieces from this comet burn up in the Earth’s upper atmosphere as Perseid meteors. Source here.

My sense of this is that Earth just passes through these comet debris tails each year (see schematic image at left) -- and typically with the "culprit" comet no where near -- so in general (with some exceptions of course) why would the debris tail create any better show than in other similar years?

Maybe I'm wrong and there are good reasons for it. I just never see anything.

OK, that's all for now. I'm not planning on updating the blog until Friday.

--Regulus

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