← All spheres

Geosphere

Net ecosystem carbon flux

Whether the corridor is releasing more carbon than is normal for the season. The CaCO₃ research quantifies how much of a source could be pulled back.

LiveTrusted
data updated 2026-10-02 19:05 KSTnext refresh --:--8/8 public sources
Forecast & calibrated interval
90% conformal · adaptive α=0.03 · for 2026-10-03
-5-2147forecast26-04-2626-07-1526-10-02gC·m⁻²·d⁻¹
Last observed · 2026-10-02
-3.26 gC·m⁻²·d⁻¹
Forecast
-2.33 gC·m⁻²·d⁻¹
90 % band
-4.14 – -0.51
Trust Core verdict
Stress sub-index
1/100
Confidence
72%
Stress band (propagated)
0.000.10 – 17100
Rationale

Inputs in-distribution, members in agreement, interval tight — the Trust Core stands behind this number.

Stress basis: NEE anomaly vs the same season in prior years: -1.99 gC·m⁻²·d⁻¹ versus the 8-year seasonal mean of -0.34.

01Calibrated uncertainty + disagreement

Ensemble spread

Six heterogeneous members — a GRU, an MLP, a ridge autoregression, Holt smoothing, a seasonal baseline and persistence — each vote on the next value. Their weighted scatter relative to the recent one-step error is the disagreement signal; wide scatter means the members have genuinely split.

seasonal
moving-avg
drift
Holt
AR(7)
m5
-4.71 gC·m⁻²·d⁻¹ensemble mean -2.33 gC·m⁻²·d⁻¹1.14 gC·m⁻²·d⁻¹

Trust signals

Ensemble disagreement0.032

Spread of members vs expected one-step error.

Out-of-distribution0.291

Standardised distance of today's 11-feature input row from the training set. Furthest feature: Recent history of the target (-3.21σ).

Confidence0.722

The combined trust the Core assigns this output.

02Explainability

What drove this prediction

Input×Gradient attribution: the gradient of the neural members' forecast with respect to every input, multiplied by the input, summed over the window — so each named driver carries a sign and a magnitude. The AR member's coefficients fold into the target's own history.

Recent history of the target+1.00

The series' own recent values (autoregressive memory)

Gross primary production+0.68

Light-use-efficiency GPP

Season (sin)−0.21

Day-of-year phase

Canopy NDVI−0.20

MODIS NDVI interpolated to the day

Shortwave radiation+0.12

ERA5 daily shortwave radiation

Vapour-pressure deficit−0.11

ERA5 daily max VPD, the drought-stress driver

30-day rainfall+0.10

Monthly rain, the soil-moisture proxy

Mean temperature−0.04

ERA5 daily mean 2 m temperature

Ecosystem respiration+0.01

Q10 respiration term

Season (cos)+0.01

Day-of-year phase

Minimum temperature+0.00

ERA5 daily minimum, the MOD17 cold-limit driver

03Open monitoring

This stream, audited

idealnominalempirical
Recent coverage (adaptive)
86%static band 78% · 90 steps
Recent MAE
0.872 gC·m⁻²·d⁻¹rolling 90-step backtest
Drift (PSI)
0.40elevated
Full monitoring →
04Horizon path + rolling backtest

7-step path

The ensemble is rolled forward recursively; each horizon carries its own conformal quantile from the calibration window, scaled by the adaptive factor, so the band widens honestly with lead time. Drivers are held at their last value and only the season advances.

-4.83-2.75-0.671.423.5010-0310-0510-0909-03last obs 10-02ensemble path (gC·m⁻²·d⁻¹)90 % band per horizon
h1 · 10-03
-2.33
[-4.14, -0.51] · held-out cov 86%
h3 · 10-05
-1.25
[-3.48, 0.97] · held-out cov 81%
h7 · 10-09
-0.17
[-2.75, 2.41] · held-out cov 81%

Rolling backtest, last 90 steps

Every point is a real one-step forecast made from the data available at the time, against what the feed then reported. Misses outside the band are marked. Adaptive conformal inference nudges α each step toward the 90 % target — currently α=0.031 (band ×1.48 vs static).

-4-114707-0507-2308-1008-2809-1510-02observed (gC·m⁻²·d⁻¹)one-step forecast90 % adaptive bandmiss
05Model card + physical layer

Model card

trained 2026-10-02

A heterogeneous ensemble: two neural networks trained by backpropagation on the archive, two classical forecasters, and two baselines every member must beat. Weights are set by validation error, never by the test window.

MemberKindWeightTest MAE*
GRU recurrent net1,941 paramsneural · recurrent
23%
0.586
MLP feed-forward net1,869 paramsneural · feed-forward
22%
0.591
AR(7) ridgestatistical
19%
0.619
Holt smoothingstatistical
16%
0.645
Seasonal naivebaseline
8%
1.101
Persistencebaseline
12%
0.605

* held-out test window, native units

Held-out MAE
0.59gC·m⁻²·d⁻¹
Persistence MAE
0.60gC·m⁻²·d⁻¹
Skill vs persistence
+3.1%beats the baseline
Test coverage (static)
86%90 % band
Time-ordered split
train 2018-01-01 → 2023-04-02 · 1918 steps
validation 2023-04-03 → 2024-02-15 (early stopping, member weights)
calibration 2024-02-16 → 2025-06-09 · 480 residuals
test 2025-06-10 → 2026-10-02 · 480 never-seen steps
Inputs · window of 14 steps
Recent history of the targetGross primary productionEcosystem respirationMean temperatureMinimum temperatureShortwave radiationVapour-pressure deficitCanopy NDVI30-day rainfallSeason (sin)Season (cos)
horizons: h1 cov 86% skill 3% · h3 cov 81% skill 10% · h7 cov 81% skill 19%

Carbon balance

The light-use-efficiency model's decomposition of today's flux, the corridor's trailing-year balance, and the global CO₂ background from Mauna Loa.

GPP today
4.40gC·m⁻²·d⁻¹
gross primary production, LUE model
Respiration today
1.13gC·m⁻²·d⁻¹
Q10 ecosystem respiration
Trailing-year balance
+115gC·m⁻²
net source over the last 365 days (modelled)
Mauna Loa CO₂
425.82ppm
2026-09-20 · +1.57 ppm year-on-year
NDVI hold
42 d
days the last MODIS composite has been carried forward
06Today's input row
z = standardised against the training window
Recent history of the target-3.264-3.21σ
Gross primary production4.396+2.68σ
Ecosystem respiration1.131-0.29σ
Mean temperature12.875+0.22σ
Minimum temperature7.45+0.13σ
Shortwave radiation19.635+0.86σ
Vapour-pressure deficit1.388+0.51σ
Canopy NDVI0.837+1.99σ
30-day rainfall13.975-0.75σ
Season (sin)-1-1.46σ
Season (cos)0.001-0.04σ

Provenance

Livenewest observation 2026-10-02lag 0 d

Governed quantity: Next-day corridor-mean net ecosystem exchange (positive = source to the atmosphere).

ERA5 / ERA5-Land reanalysis (Open-Meteo archive)
Daily temperature, humidity, VPD, precipitation, wind, shortwave radiation, ET₀
ECMWF Copernicus · Open-Meteo
daily · latency ≈1 day (preliminary), 5 days (final)
archive 1940 → present
live: 6 sites, 11 days
source ↗
MODIS MOD13Q1 vegetation index (ORNL DAAC subset service)
250 m NDVI, 16-day composite, with pixel reliability QA
NASA · ORNL DAAC
16-day composite · latency ≈2–3 weeks
archive 2000 → present
live: archive is current (no newer composite published)
source ↗
NOAA GML Mauna Loa CO₂
Weekly atmospheric CO₂, ppm
NOAA Global Monitoring Laboratory
weekly · latency 1 week
archive 1974 → present
live: 425.82 ppm
source ↗

archive pulled 2026-10-02 09:54 UTC · live tail merged at request time · all sources publicly available · nothing on this page is simulated