Memorial Hall CO2

We are streaming (and archiving) CO2 levels we are measuring in air from outside Memorial Hall, located here.  The actual Licor 820 analyzer we use is located in Room 7130, approximately where the “M” in Memorial is in this map:

The analyzer is connected to a small, 12V, ~$20 aquarium pump (Halper Mini Pump, Type: GSV2512N), which we power via an AC adapter.

Values are read every 12 seconds, and then averaged to produce this up-to-the-minute badge.  We calibrate the instrument regularly, using both 0 ppm “zero” gas and 1000 ppm calibration gas (a 1-point span).  Check the FAQ for when the instrument was last calibrated.
 

As a graduate student in 1958, Dave Keeling started measuring the concentrations of atmospheric carbon dioxide in flasks he filled from atop Mauna Loa, Hawaii (http://news.bbc.co.uk/2/hi/science/nature/7120770.stm).
In March 1958, Keeling measured CO2 at levels of about 313 parts per million (http://scrippsco2.ucsd.edu/program_history/keeling_curve_lessons_2.html).  As of last week, CO2 levels from Mauna Loa were at 390 parts per million (ppm; http://www.esrl.noaa.gov/gmd/ccgg/trends/weekly.html).

 

One of the most remarkable legacies of Keeling’s work is that we can trace the general increase in carbon dioxide emissions associated with increased fossil fuel use–through measurements of CO2 from Hawaii!

 

A second legacy is that–every year–we can see when vegetation in the Northern Hemisphere is photosynthesizing.  In late Spring and Summer, “global” CO2 levels decline.  When our hemisphere loses its leaves every Fall, CO2 levels increase more dramatically.

 

Global monitoring of CO2 occurs (e.g., map at http://www.esrl.noaa.gov/gmd/dv/iadv/), but to our knowledge, there is no real-time reporting of CO2 from anywhere within the triangle defined by Indiana, coastal North Carolina, and coastal New Jersey.

 

This monitoring project –a very modest “Keeling curve” for Harrisonburg– was facilitated through a collaboration between JMU Center for Instructional Technology staff, notably Andreas Knab. A <script> has been written that intercepts an XML feed from a Licor 820 infrared gas analyzer that has been positioned to sample from outside the ground floor of Memorial Hall every 12 seconds; values are averaged over a minute, and reported out to this badge (http://cit.jmu.edu/co2/badge.png) and stored on a CIT server, for community download as comma separated values in multiple formats, from all available data (http://cit.jmu.edu/co2/month-201006.csv) to the current month’s data (http://cit.jmu.edu/co2/month.csv).

 

The Memorial Hall data show a very strong diurnal cycle of carbon dioxide, in some cases up to 100 ppm.  Sufi Nawaz generated this graph of CO2 concentrations (ppm) the week of 4 October 2011:

Caveat emptor: we are trying to figure out how to get the thin gray vertical lines to correspond to midnight, instead of 20:00 or 8 pm.

You can create a similar graph for any week for which data exist here. Time series data for parsing seasonal and monthly differences are here.

 

Webpages can link to the Memorial Hall badge, which updates every minute (step-by-step WordPress instructions?); this provides a higher resolution record than this type of widget available from co2now.org.

Sufi, could you insert this

CO2 widget here?
 

There is a lot more information here at the Scripps website.

 

We are working on cleaning this tool up.  Stay tuned.

CO2 graphs (2012)

CO2 right now

http://cit.jmu.edu/co2/badge.png

CO2 graphs (2011)

CO<sub>2</sub> graphs (2011)

Please note the straight lines (eg July 7-September 17) represent missing data due to, for example, instrument malfunction or use for other purposes (see FAQ).  No details are provided for times of missing data: graph is not “clickable” for these … Continue reading →

CO2 data

CO<sub>2</sub> data

Carbon dioxide (parts per million) data are measured every 12 seconds, averaged every minute, and recorded/stored on a JMU Center for Instructional Technology web server every minute. You can download–as a comma separated values (.csv) file–the current month of data … Continue reading →

Memorial Hall CO2 blog

Here are notes from our conversation today (Sept. 1, 2011). A page on this website will provide dynamic graphs of CO2 levels outside Memorial Hall.  These might be a daily graph, a weekly graph, and an annual graph. Here are … Continue reading →

Memorial Hall CO2 FAQ

Memorial Hall CO<sub>2</sub> FAQ

1. Why are you measuring CO2 levels outside Memorial Hall? 2. How are you measuring CO2 levels outside Memorial Hall? 3. How can I download historical data? 4. Why isn’t the CO2 timestamp current? 5. How did you get this … Continue reading →

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