Partager

Bilan des gaz à effet de serre présents dans l'atmosphère, d'après les observations effectuées à l'échelle du globe en 2009.

The state of greenhouse gases in the atmosphere based on global observations through 2009.

Auteurs : WMO (World Meteorological Organization)

Type d'article : Article

Résumé

The latest analysis of observations from the WMO Global Atmosphere Watch Programme shows that the globally averaged mixing ratios of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) reached new highs in 2009, with CO2 at 386.8 ppm, CH4 at 1803 ppb and N2O at 322.5 ppb. These values are greater than those in pre-industrial times (before 1750) by 38, 158 and 19%, respectively. Atmospheric growth rates of CO2 and N2O in 2009 are consistent with recent years, but are lower than in 2008. After nearly a decade of no growth, atmospheric CH4 has increased during the past three years. The reasons for renewed growth of atmospheric methane are not fully understood, but emissions from natural sources (from northern latitudes and the tropics) are considered potential causes. The NOAA Annual Greenhouse Gas Index shows that from 1990 to 2009, radiative forcing by all longlived greenhouse gases increased by 27.5%, with CO2 accounting for nearly 80% of this increase. The combined radiative forcing by halocarbons is nearly double that of N2O. See also this Bulletin, references 2010-2076 to 2080.

Détails

  • Titre original : The state of greenhouse gases in the atmosphere based on global observations through 2009.
  • Identifiant de la fiche : 2010-2075
  • Langues : Anglais
  • Sujet : Environnement, Généralités, Alternatives aux HFC
  • Source : WMO Greenh. Gas Bull. - n. 6
  • Date d'édition : 24/11/2010

Liens


Voir d'autres articles du même numéro (3)
Voir la source

Indexation