Answer: The current weekly average CO2 at Mauna Loa is 428.57 ppm for the week beginning on November 01, 2026, last updated November 11, 2026.
Status: Confirmed
Entry: science/co2
Revision: 1
Digest: sha256:701082f9ea12bd3b (changes whenever the content changes)

Timeline:
  Created: 2026-11-12T10:37:23Z
  Last changed: 2026-11-12T10:37:23Z
  Last verified: 2026-11-12T11:34:20Z
  Next check: 2026-11-13T11:34:20Z
  Check interval: Daily
  Expected change: No fixed schedule

Data:
  Field | Value | Unit | Source | As of
  Weekly average CO2 at Mauna Loa | 428.57 | ppm | [1] | 2026-11-12
  Week beginning | November 01, 2026 |  | [1] | 2026-11-12
  Last updated | November 11, 2026 |  | [1] | 2026-11-12
  Weekly value from 1 year ago | 425.21 | ppm | [1] | 2026-11-12
  Weekly value from 10 years ago | 403.06 | ppm | [1] | 2026-11-12

Sources:
  [1] NOAA Global Monitoring Laboratory. "Trends in CO2 - NOAA Global Monitoring Laboratory". https://gml.noaa.gov/ccgg/trends/weekly.html
      Role: primary. Accessed: 2026-11-12T11:34:20Z
      Quote: "Week beginning on November 01, 2026: 428.57 ppm" (Supports: Weekly average CO2 at Mauna Loa, Week beginning)
      Quote: "Last updated: November 11, 2026" (Supports: Last updated)
      Quote: "Weekly value from 1 year ago: 425.21 ppm" (Supports: Weekly value from 1 year ago)
      Quote: "Weekly value from 10 years ago: 403.06 ppm" (Supports: Weekly value from 10 years ago)
      Snapshot SHA-256: 5c9573942488e411876ca30564f6280fd5f1a3919e60affe293696db76bda8ca (captured 2026-11-12T10:37:23Z)

Verification:
  Method: Automated extraction from [1] with deepseek-flash (JSON output, thinking disabled). Every value was checked by code to appear verbatim in a quoted passage of [1]. On this check the text of [1] was unchanged since 2026-11-12T10:37:23Z, so the values verified then were kept.
  Cross-check: not-available at 2026-11-12T11:34:20Z. No independent second source is configured for this entry
  Last successful check: 2026-11-12T11:34:20Z
  Last attempt: 2026-11-12T11:34:20Z

Notes and limitations:
  Extracted automatically from a single official source.

Change log:
  Time | Event | Change | Source
  2026-11-12T10:37:23Z | added | Entry created | —
  Changes for this entry as a feed: https://latestn.com/science/co2/latest

Challenge this entry:
  Open challenges: None
  How: If a value here is wrong or out of date, send what is wrong and a link to evidence. Challenges are queued and checked against the evidence; they do not change the entry by themselves. If the entry changes as a result, the change log says so.
  Form: https://latestn.com/dispute/science/co2
  POST: https://latestn.com/dispute/science/co2 with claim, evidence_url, and optionally field and contact (form-encoded or JSON)
  GET: https://latestn.com/dispute/science/co2?claim={what is wrong}&evidence_url={link}

How to cite:
    latestN. (2026). What is the current atmospheric CO2 concentration? Revision 1, last verified 2026-11-12T11:34:20Z. https://latestn.com/science/co2 (accessed 2026-11-12T12:52:42Z).

    @misc{latestN_science_co2_r1,
      title        = {What is the current atmospheric CO2 concentration?},
      author       = {{latestN}},
      year         = {2026},
      howpublished = {\url{https://latestn.com/science/co2}},
      note         = {Revision 1; digest sha256:701082f9ea12bd3b; last verified 2026-11-12T11:34:20Z; accessed 2026-11-12T12:52:42Z}
    }

URL: https://latestn.com/science/co2