Carbon Dioxide Levels

The current level of carbon dioxide in the Earth’s atmosphere is about 440 parts per million (ppm). The CO2 levels are officially measured at three “pristine” sites: Mauna Loa, HI; Barrow, AK; and Grimes Point, Tasmania. However, levels encountered in some of our day-to-day experiences are higher. OSHA set the acceptable level of CO2 in the workplace to 1000 parts per million. However, this is often exceeded in some office buildings, schools, and homes.

Each and every one of us exhales CO2 at a level of about 40000 ppm. It follows that in some poorly ventilated enclosures that levels of CO2 are above 1000 ppm. Some office meeting rooms are at 1900 ppm or more. Airliners in flight have levels around 1400 ppm. Cars with recirculated air can reach a level that is 4 times the acceptable level.

Effects of CO2 in the air:

• <150 ppm: all vegetation dies

• 400 ppm: background (normal) outdoor air level

• 400-1,000 ppm: typical levels found in occupied spaces with good air exchange

• 1,000-2,000 ppm: level associated with complaints of drowsiness and poor air

• 2,000-5,000 ppm: level associated with headaches, sleepiness, and stagnant, stale, stuffy air; poor concentration, loss of attention, increased heart rate and slight nausea may also be present.

• >5,000 ppm: This indicates unusual air conditions where high levels of other gases also could be present. Toxicity or oxygen deprivation could occur. This is the permissible exposure limit for daily workplace exposures.

• >40,000 ppm: This level is immediately harmful due to oxygen deprivation.

This would explain why some people nod off during meetings and in class. The dangers of high levels in unventilated cars are obvious.

The efforts to make office buildings and homes more energy efficient have made them more airtight. This has caused the CO2 levels to increase within. The new LEED standards include air quality standards to mitigate the effects of high CO2 levels.

One double-blind study shows that high CO2 levels also have a profound effect on our cognitive ability (Allen et al. 2015). The study found that the decision-making performance of working professionals became impaired at high CO2 levels. Averaged across all metrics, performance was reduced by 15% at 945 ppm and 50% at 1400 ppm compared to the 550 ppm control.

The annual increase in carbon dioxide levels is about 2 ppm. At that rate, it would take over four centuries to double the current concentration. However, in reality, vegetation would increase and absorb more carbon. So, another way to mitigate CO2 levels is to introduce more plants inside office buildings, homes, and schools.

References:

Allen, J.G., MacNaughton, P., Satish, U., Santanam, S., Vallarino, J., Spengler, J.D., Environmental Health Perspectives 124, 805 (2015).

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Autumn of 2017: Weather Summary

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Meteorological autumn has ended. Here is a summary of the fall’s weather in Stormstown, PA.

Overall, it was a warmer than average fall, especially during October. September was near normal, just 0.4 deg F above normal. October was much above normal at 4.6 deg above normal, even though there were 3 days with a minimum temperature of 32 deg. F or less.  However, November was 2.6 deg F below normal, with 23 days with a minimum temperature of 32 deg F or less. The first day with a temperature below freezing was October 17.

Precipitation was below normal for the most part, even though October was 1.7 inches above normal. The maximum single day rainfall was 1.91 inches on October 29.

Highest wind speed was 35 mph on November 19.

First Snowfall of the Season

First snowfall of the season in Stormstown, PA. The forecast today called for a chance of snow showers (60%). Instead, there was moderate snow, starting around 10 AM EST. Later, the flakes started to fall in clumps.

Air temperatures remained well above freezing for most of the day, so there was little or no accumulation in the area. However, to the southwest, in The Laurel Highlands, travel was affected significantly.

Flight 93 National Memorial

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Today, my wife and I traveled to The Flight 93 National Memorial near Shanksville, PA. The memorial is about a 90 minute drive from our home in Stormstown. It was fitting that the weather was very much like that day on September 11, 2001.

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Black granite marks the final flight path of Flight 93 before impact at 10:03 AM EDT, September 11, 2001.

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The black granite path passes through the outside walls of the visitor center.

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The visitor center sits at the top of a hill, overlooking Memorial Plaza, the crash site and the 40 acre debris field. This is the final resting place of the 40 passengers and crew. The Red Cross gave each of the families of the passengers and crew a small vial of soil from the debris field.

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The visitor center as seen from Memorial Plaza. This was the site of The FBI command post during their investigation into the crash. It was also the site of the temporary memorials, which are now housed inside the visitor center.

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Black granite continues to mark the final flight path at the foot of the hill from the visitor center at The Memorial Plaza.

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At The Memorial Plaza, the names of the 40 passengers and crew of Flight 93 are memorialized in slabs of marble.

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Todd Beamer was one of the passengers that attempted to take over the cockpit from the hijackers. His last words, heard by cell phone by an airline representative, were, “Let’s roll!” His Oracle ID card survived the impact and is on display inside the visitor center.

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A 17-ton boulder was placed by the point of impact.C7A5F819-155D-451F-6727AF151DF7D841-largeThe largest recovered piece of the Boeing 757-222 aircraft measured just a few feet on a side. Most of the debris was strewn over 40 acres. Lightweight paper items were found as far away as New Baltimore, eight miles away. Some of the debris is on display inside the visitor center. I only recognized parts of a scarred circuit board and some wire. Also on display are a drivers license and some ID cards. The impact made a crater 30 feet across and 15 feet deep. The plane hit at an angle of 40 degrees, at nearly 600 mph in an inverted attitude. The cockpit voice recorder and the flight recorder survived, and the recovered data contained a record of the aircraft’s entire flight. Portions are shown inside the visitor center in a flight simulator display.

Centre County Pennsylvania Senior Environmental Corps

This week, I became a permanent member of a test team for The Centre County Pennsylvania Senior Environmental Corps. I have previously been out twice with a team that samples and tests the water from Little Fishing Creek at two sites in Centre County. Data obtained from these and other sites can be found here.

Little Fishing Creek is part of The Chesapeake Bay Watershed. The stream flows into Fishing Creek, The West Branch of The Susquehanna River, the main river and then into The Chesapeake.

Amateur Radio Traffic Net

Last Week, I became a regular check-in to The Western Pennsylvania Phone Traffic Net. I started to look for a net after the landfall of Hurricane Harvey. The net meets every evening at 6 PM on 80-meters, and is part of The National Traffic System (NTS).

So far, I’ve initiated 4 radiograms. I hope to continue handling NTS messages on a regular basis.

Harvey and Irma Are Not A Sign of Climate Change

at201711_sat Sorry climate alarmists, but you can not blame this year’s major hurricanes on climate change, global warming or whatever you want to call it.

Posting on the Watts Up With That blog.

Prior to this season, there haven’t been any major hurricane landfalls in The United States since Wilma in 2005. This season is simply an anomaly. In fact, the frequency of major hurricanes has been decreasing.