Atmospheric Sulfur Hexafluoride (SF6)

Common Questions

What is Sulfur Hexafluoride (SF6)?

Sulfur hexafluoride or sulphur hexafluoride is an inorganic compound with the formula SF₆. It is a colorless, odorless, non-flammable, and non-toxic gas. SF ₆ has an octahedral geometry, consisting of six fluorine atoms attached to a central sulfur atom. It is a hypervalent molecule.

Source: https://en.wikipedia.org/wiki/Sulfur_hexafluoride

What is Carbon Dioxide (co2) used for?

Carbon dioxide is used as a refrigerant, in fire extinguishers, for inflating life rafts and life jackets, blasting coal, foaming rubber and plastics, promoting the growth of plants in greenhouses, immobilizing animals before slaughter, and in carbonated beverages. And most improtantly it is food for all plants on earth.

What does PPT mean?

PPT is an abbreviation for "parts per trillion".

One ppm is equivalent to the absolute fractional amount multiplied by one million. A better way to think of ppm is to visualize putting four drops of ink in a 55-gallon barrel of water and mixing it thoroughly. This procedure would produce an ink concentration of 1 ppm. Some other analogies that may help you visualize the scale involved with ppm. One ppm is like:

• one inch in 16 miles,
• one second in 11.5 days,
• one minute in two years.

An even smaller concentration measurement is parts per billion (ppb). One ppb is one part in 1 billion. Because a ppb is a much lower concentration, some analogies would be :

• one sheet in a roll of toilet paper stretching from New York to London,
• one second in nearly 32 years, or
• one pinch of salt in 10 tons of potato chips.

Source: 🇦🇺 https://www.adelaide.edu.au/arcpoh/dperu/fluoride/ppm.html

Data Information

Uncertainties in the global monthly means are estimated using two terms: The first is a bootstrap (resampling) method that varies the sites in our network. Each pseudo-network contains the same number of sites as our actual NOAA ESRL cooperative global air sampling network, but some are repeated and some are excluded. The second term is a Monte Carlo method that randomly modifies the data to account for measurement uncertainty. In both cases, 100 globally-averaged time series are created. Standard deviations of the monthly means are calculated, and the two terms (network and analytical) are taken in quadrature to give the reported uncertainties. A default value (-9.9) indicates the uncertainty has not yet been calculated for that month. Please see Dlugokencky et al., 1994, JGR, vol. 99, 17021-17043, for a complete discussion.

SF6 expressed as a mole fraction in dry air, picomol/mol, abbreviated as PPT.

NOTE: In general, the data presented for the last year are subject to change, depending on recalibration of the reference gas mixtures used, and other quality control procedures. Occasionally, earlier years may also change for the same reasons. Usually these changes are minor.

Data Source

NOAA / Global Monitoring Laboratory (Earth System Research Laboratories)

https://gml.noaa.gov/ccgg/trends_sf6/

Data Gathering Locations

We make use of the global mean of atomospheric CO2 which is gathered by four observatories across the world.

Mauna Loa Observatory, Hawaii. (19.5364° N, 155.5765° W)