Correspondences
What is linked, what is not
Each arc joins two phenomena tested on this site. Green and animated: clear link (correlation significant at 5 % after correcting for autocorrelation, or a response outside chance in an event study). Grey: inconclusive test. A statistical link alone does not establish causation.
- Clear link
- Inconclusive
Hypotheses tested
16
Clear links
11
Causation demonstrated
0
Arc width from |r| of the stored result; several tests between the same phenomena are drawn as stacked arcs.
Hypothesis tested: El Niño droughts and tropical fires reduce the land carbon uptake: the CO₂ rise accelerates in the following months (Bacastow, 1976; Jones et al., 2001).
Pearson correlation r (lag 8 month(s))
0.52
95% interval [0.38; 0.62] (block bootstrap)
Aligned points
803
effective n ≈ 150 (autocorrelation)
p-value
0.00000
two-sided, Fisher z transform, effective n
Period analysed
1959-03 → 2026-09
computed on Oct 23, 2026 · engine v1.0
Aligned series (standard deviations, after preprocessing)
Show the data as a table
Correlation by lag (month(s))
Show the data as a table
Method and sources
The growth is the difference CO₂(t) − CO₂(t − 12 months) of the NOAA deseasonalised series; both series are filtered (10-year high-pass). Pearson correlation for lags of −12 to +12 months, Bretherton et al. effective size, 12-month block bootstrap.
Computation parameters
{
"growth": "CO2(t) − CO2(t − 12 months), deseasonalised series",
"max_lag": 12,
"bootstrap": {
"seed": 20261023,
"block": 12,
"draws": 1000
},
"statistic": "pearson",
"high_pass_months": 120
}Inputs : psl.nino34.anom.monthly (945 pts, run #42) · gml.co2.deseasonalized.monthly (823 pts, run #16)
Reading this result
The 12-month growth is centred six months before its end date: part of the lag found (about 8 months) comes from that convention; the physical lag is about two to four months. Human emissions set the trend; El Niño only modulates the rate. Correlation is not causation: common factors (seasons, cycles, trends) or coincidence can produce it. The p-values account for autocorrelation (effective n) but not for preprocessing choices; the confidence interval comes from a block bootstrap. The limits of the source data apply.
SOURCES OF THIS PAGE
- Niño 3.4 SST anomaly (NOAA PSL, ERSSTv5)
-
NOAA PSL, Niño 3.4 index: monthly SST anomaly (5°N–5°S, 170°–120°W) from ERSSTv5, climatology 1991–2020.
· source page ↗
Licence : U.S. Government work, public domain · retrieved on Oct 23, 2026 · SHA-256 879cf3cb31d7… - Mauna Loa monthly mean CO₂ (NOAA GML)
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Lan, X., Tans, P., & Thoning, K. W. (2026). Trends in globally-averaged CO₂ determined from NOAA Global Monitoring Laboratory measurements; Mauna Loa monthly mean, after Thoning et al. (1989).
· doi:10.1029/JD094iD06p08549 · source page ↗
Licence : U.S. Government work, public domain; cite Lan, X., Tans, P. & Thoning, K. W., NOAA GML · retrieved on Oct 23, 2026 · SHA-256 d895fb5b4a59… - Bacastow (1976)
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Bacastow, R. B. (1976). Modulation of atmospheric carbon dioxide by the Southern Oscillation. Nature, 261, 116–118.
· doi:10.1038/261116a0
Licence : Published literature; cited - Jones et al. (2001)
-
Jones, C. D., Collins, M., Cox, P. M., & Spall, S. A. (2001). The carbon cycle response to ENSO: a coupled climate–carbon cycle model study. Journal of Climate, 14(21), 4113–4129.
· doi:10.1175/1520-0442(2001)014<4113:TCCRTE>2.0.CO;2
Licence : Published literature; cited