Sentences with phrase «recent atmospheric measurements»

Variations of deuterium (δD; black), a proxy for local temperature, and the atmospheric concentrations of the greenhouse gases CO2 (red), CH4 (blue), and nitrous oxide (N2O; green) derived from air trapped within ice cores from Antarctica and from recent atmospheric measurements (Petit et al., 1999; Indermühle et al., 2000; EPICA community members, 2004; Spahni et al., 2005; Siegenthaler et al., 2005a, b).

Not exact matches

That is the case whether you are extrapolating from paleoclimate data or from any recent temperature dataset vs atmospheric CO2 concentration measurements (eg Keeling curve).

We find (i) measurements at all scales show that official inventories consistently underestimate actual CH4 [methane] emissions, with the natural gas and oil sectors as important contributors; (ii) many independent experiments suggest that a small number of «super-emitters» could be responsible for a large fraction of leakage; (iii) recent regional atmospheric studies with very high emissions rates are unlikely to be representative of typical natural gas system leakage rates; and (iv) assessments using 100 - year impact indicators show system - wide leakage is unlikely to be large enough to negate climate benefits of coal - to - natural gas substitution.

That is the case whether you are extrapolating from paleoclimate data or from any recent temperature dataset vs atmospheric CO2 concentration measurements (eg Keeling curve).

Scenario B1 assumes a continuation of the compounded annual growth rate in atmospheric CO2 of the most recent period and the period since Mauna Loa measurements started in 1958 (a bit more than 0.4 % per year CAGR).

Ernst Beck has complied tens of thousands of analyses of early measurements of atmospheric CO2, and concludes that CO2 levels were much higher during the 1930's warm period than the generally - accepted levels; CO2 dropped sharply during the cooling from ~ 1946 to ~ 1977; and CO2 increased since 1977 due to the recent warming, and is now at similar levels to the early 1940's.

«Since 1990, surface ocean pH has directly been measured or calculated at several locations, with the average recent decrease estimated as 0.0019 pH units per year at the Hawaii Ocean Time - series (HOT; close to the site of long - term atmospheric CO2 measurements at Mauna Loa)[12]; 0.0017 per year based on transects in the North Pacific [13]; 0.0012 per year at the Bermuda Atlantic Time - Series (BATS)[14] and 0.0017 per year at the European Station for Time - Series in the Ocean at the Canary Islands (ESTOC)[15].

Also, while we have good atmospheric measurements of other key greenhouse gases such as carbon dioxide and methane, we have poor measurements of global water vapor, so it is not certain by how much atmospheric concentrations have risen in recent decades or centuries, though satellite measurements, combined with balloon data and some in - situ ground measurements indicate generally positive trends in global water vapor.»

There are no measurements of DIC which could reliably indicate its global change during the recent period of rising atmospheric CO2 concentration.

This parallels a recent NOAA study of atmospheric methane measurements that found that «methane emissions from natural gas as a fraction of production have declined from approximately 8 per cent to approximately 2 per cent over the past three decades» — with production soaring in recent years.

Measurements of air in ice cores show that for the past 800,000 years up until the 20th century, the atmospheric CO2 concentration stayed within the range 170 to 300 parts per million (ppm), making the recent rapid rise to nearly 400 ppm over 200 years particularly remarkable [figure 3].

By examining temperature measurements from nearby, researchers know that tree growth at these locations tracked atmospheric temperatures for much of the twentieth century and then diverged from the actual temperatures during recent decades.

Measurements of air in ice cores show that for the past 800,000 years up until the 20th century, the atmospheric CO2 concentration stayed within the range 170 to 300 parts per million (ppm), making the recent rapid rise to nearly 400 ppm over 200 years particularly remarkable (see Figure 3).