Globally Averaged Marine Surface Annual Mean CO2 Growth Rates

$0 / year

This dataset contains the Annual Mean Growth Rate (AMGR) trends in globally distributed networks of air sampling sites from 1959 till 2016. It contains estimated data for every single year during the given period around the globe.

Categories: ,
Complexity

This dataset is sourced from the US Government’s Earth System Research Laboratory (ESRL), Global Monitoring Division (GMD). The study under discussion comprises of the Global Annual Mean Growth Rate series from 1959 through 2016.

The annual mean rate of growth of CO2 in a given year is the difference in concentration between the end of December and the start of January of that year. It represents the sum of all CO2 added to, and removed from, the atmosphere during the year by human activities and by natural processes. The annual mean growth during the previous year is determined by taking the average of the most recent December and January months, corrected for the average seasonal cycle, as the trend value for January 1, and then subtracting the same December-January average measured one year earlier. Our first estimate for the annual growth rate of the previous year is produced in February of the following year, using data through November of the previous year. That estimate will then be updated in March using data from December, and again in April using data through January. The estimation for the growth rate of the previous year are finalized in the fall of the following year because a few of the air samples on which the global estimate is based are received late in the following year.

The values in this dataset are subject to change depending on quality control checks of the measured data, but any revisions are expected to be small. The estimates of the global mean CO2 concentration, and thus the annual growth rate, are updated every month as new data come in. The statistics are as follows. If we estimate during a given month (“m”) the global average CO2 during the previous month (“m-1”), the result differs from the estimate made (up to almost a year later) when all the data are in, with a standard deviation of 0.57 ppm. For month m-2, the standard deviation is 0.17 ppm, and for month m-3 it is 0.10 ppm. We decided to provide the global mean estimates with a lag of two months. Thus, a December average is first calculated during the following February.

The estimated uncertainty in the global annual mean growth rate varies by year, and has been estimated by a bootstrap technique for 1980 and later. One hundred different realizations of a global network were constructed by randomly picking sites, with restitution, from our existing marine boundary layer sites in the National Oceanic and Atmospheric Administration (NOAA)/ESRL cooperative air sampling network (Conway, 1994). Each member of the ensemble of networks has the same number of sites as the real network, but some sites are missing, while others are represented more than once. An additional condition is that at least one southern high latitude site is present, one tropical and one northern high latitude site, because the researchers have always maintained broad latitude coverage in the real network. Temporal data gaps at individual sites are present in the bootstrap networks. The reported uncertainties are the 1-sigma standard deviations for each year’s growth rate of the ensemble members. Pre-1980 the annual growth rate and uncertainty have been calculated from the average of the Mauna Loa and South Pole records (before 1974 as measured by the Scripps Institution of Oceanography), as detailed in Ballantyne et al. (2012).

Date Created

2017-07-05

Last Modified

2017-07-05

Version

2017-07-05

Update Frequency

Annual

Temporal Coverage

N/A

Spatial Coverage

N/A

Source

John Snow Labs => Earth System Research Laboratory

Source License URL

John Snow Labs Standard License

Source License Requirements

N/A

Source Citation

Ed Dlugokencky and Pieter Tans, NOAA/ESRL

Keywords

Global CO2 Trends, Atmospheric CO2, Annual Mean Growth Rate, Trend values

Other Titles

Global Annual Mean CO2 Growth Rates Time Series over Marine Surface, Global Annual Mean Growth Rates CO2 Trends from 1959 till Present, Marine Surface Annual Mean CO2 Growth Rates Trend around the Globe

Name Description Type Constraints
Recorded_YearRefers to the specific year when the particular data is recorded.daterequired : 1
Annual_Increase_CO2Annual CO2 mole fraction increase parts per million (ppm) from Jan 1 through Dec 31.numberrequired : 1 level : Ratio
Uncertainty_CO2The uncertainty in the global annual mean growth rate is estimated using a monte carlo technique that computes 100 time series of global annual growth rates, each time using measurement records from a different sampling of sites from the NOAA ESRL cooperative air sampling network.numberrequired : 1 level : Ratio
Recorded_YearAnnual_Increase_CO2Uncertainty_CO2
19590.960.31
19600.710.27
19600.710.27
19600.710.27
19600.710.27
19600.710.27
19600.710.27
19600.710.27
19600.710.27
19600.710.27