--- attributes: ~ cited_by: [] contributors: [] create_dt: 2013-11-19T17:32:00 description: ~ display_name: 7f1ee41d-1fa8-41af-9b92-19f05ff74d00 figures: - attributes: ~ caption: 'Present-day atmospheric levels of carbon dioxide, methane, and nitrous oxide are notably higher than their pre-industrial averages of 280, 0.7, and 0.27 parts per million (ppm) by volume, respectively (left). Air sampling data from 1958 to 2013 show long-term increases due to human activities as well as short-term variations due to natural biogeochemical processes and seasonal vegetation growth (right). (Figure sources: (left) Forster et al. 2007f2b357c2-f4ae-4868-a058-e48fbdbb1303; (right) Scripps Institution of Oceanography and NOAA Earth Systems Research Laboratory).' chapter_identifier: appendix-climate-science-supplement create_dt: 2013-11-19T17:32:00 identifier: heattrapping-gas-levels lat_max: ~ lat_min: ~ lon_max: ~ lon_min: ~ ordinal: 4 report_identifier: nca3 source_citation: ~ submission_dt: ~ time_end: ~ time_start: ~ title: Heat-Trapping Gas Levels url: http://nca2014.globalchange.gov/report/appendices/climate-science-supplement/graphics/heat-trapping-gas-levels usage_limits: Free to use with credit to the original figure source. files: - display_name: app-fig4_b.png file: 05/34/8011cf6b9310cd4f4b4a9698a0b5/app-fig4_b.png href: http://data.globalchange.gov/assets/05/34/8011cf6b9310cd4f4b4a9698a0b5/app-fig4_b.png identifier: 519026ad-904e-476e-8d0d-b3ad3e935453 landing_page: ~ location: ~ mime_type: image/png sha1: 60e673e0b151a38b8075a76c360d69652038322d size: 55965 thumbnail: 05/34/8011cf6b9310cd4f4b4a9698a0b5/.thumb-519026ad-904e-476e-8d0d-b3ad3e935453.png thumbnail_href: http://data.globalchange.gov/assets/05/34/8011cf6b9310cd4f4b4a9698a0b5/.thumb-519026ad-904e-476e-8d0d-b3ad3e935453.png type: file uri: /file/519026ad-904e-476e-8d0d-b3ad3e935453 url: http://data.globalchange.gov/assets/05/34/8011cf6b9310cd4f4b4a9698a0b5/app-fig4_b.png href: http://52.38.26.42:8080/image/7f1ee41d-1fa8-41af-9b92-19f05ff74d00.yaml identifier: 7f1ee41d-1fa8-41af-9b92-19f05ff74d00 lat_max: ~ lat_min: ~ lon_max: ~ lon_min: ~ parents: [] position: ~ references: [] submission_dt: ~ time_end: 2013-12-31T23:59:59 time_start: 1958-01-01T00:00:00 title: 'Heat-Trapping Gas Levels - Right' type: image uri: /image/7f1ee41d-1fa8-41af-9b92-19f05ff74d00 url: ~ usage_limits: ~