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Four evidence-based papers using one framework (preconditions, triggers, amplifiers, suppressors, feedbacks, consequences), graded on event-specific evidence, with verified references. Primary index: NOAA's Relative ONI (RONI).
Research papers on every 2026 storm that reached hurricane or typhoon strength in the Atlantic, eastern and central Pacific and western Pacific, written newest first in batches of five. Built from IBTrACS tracks, NOAA OISST and the forecast centres' own analyses; provisional until the official reports.
Solid lines: Oceanic Niño Index (ONI; ERSSTv6 Niño 3.4, 3-month running mean, centred base periods). Dashed lines: Relative ONI (RONI; Niño 3.4 minus the 20°N–20°S tropical mean, rescaled), NOAA's official index since 1 Feb 2026. Aligned from DJF of each onset year; 2026 is the thick blue line.
| 1982–83 | 1997–98 | 2015–16 | 2026 | |
|---|---|---|---|---|
| Start (ONI, DJF) | −0.1, neutral | −0.4, weak La Niña | +0.7, already warm after the 2014 false start | −0.4, weak La Niña |
| By JAS (ONI) | +1.0, slow | +1.8, fast | +1.7, steady | +2.2, fastest |
| Peak ONI | +2.1 (DJF) | +2.4 (NDJ) | +2.6 (NDJ), highest ONI on record | Still rising; peaks usually Nov–Jan |
| Start (RONI, DJF) | +0.11, neutral | −0.21, neutral | +0.54, already at the El Niño threshold | −0.91, weak La Niña |
| By JAS (RONI) | +1.14 (rise +1.03) | +1.84 (rise +2.05), highest at this stage | +1.54 (rise +1.00) | +1.69 (rise +2.60), largest rise |
| Peak RONI | +2.40 (DJF), highest of the three on RONI | +2.28 (NDJ) | +2.25 (NDJ); the ONI–RONI gap shows much of 2015's ONI was tropics-wide warmth | Still rising. CPC forecast: 54% (SON), 83% (OND), 70% (NDJ) chance of RONI ≥ +2.5, a historic event |
| Niño 1+2 max (monthly) | +4.0, late (Jun 1983) | +3.7 (Nov) | +2.5 (Jul) | +4.7 (Sep), record |
| Subsurface heat max | — | +2.56 (Oct) | +1.97 (Aug) | +3.39 (Sep), record |
| PDO (Sep) | +0.5 | +1.8 | +1.0 | −1.55 |
| How it unfolded | Unforecast; grew slowly, then surged in autumn and lingered off South America into mid-1983. El Chichón's volcanic haze confused satellite readings. | Strong spring wind bursts sent huge Kelvin waves east; a classic east-based event that peaked in December and collapsed into La Niña by mid-1998. | Began warm, grew steadily and peaked in the central Pacific with weaker coastal warming; Southern California's winter was drier than expected. | Explosive spring–summer growth from La Niña, record coastal and subsurface warmth, strong atmospheric coupling (3-month SOI −1.8), but a negative PDO and a much warmer background ocean. |
| Marine life | Galápagos corals lost about 95% of their living tissue. Galápagos penguins fell 77% and flightless cormorants 49%. | The first global coral bleaching on record killed about 16% of the world's reefs in nine months. Galápagos penguins fell 65%. California's market squid catch collapsed from 70,257 t (1997) to under 3,000 t (1998). | Overlapped the 2014–16 "Blob" marine heatwave, so effects are shared. A record toxic algal bloom delayed West Coast Dungeness crab seasons; 8,112 starving California sea lion pups stranded (2013–16). In 2016 fewer than 10% of Great Barrier Reef reefs escaped bleaching. | Phytoplankton down in the central equatorial Pacific (NASA PACE, June). Peru's anchoveta fishery repeatedly suspended. Galápagos coral heat stress peaked at 24.6 °C-weeks in May and was still 12.1 on 15 Oct, well above the 8 at which NOAA warns of severe bleaching. |
| Did it recover? | Slowly and only in part. By 2004 the Galápagos penguins were still below half their pre-1982 number. Some Galápagos reefs have regrown; others were lost and have not come back. | Fish fast, the rest slowly. In the cool La Niña of 1999 the squid catch hit a record 90,322 t, more than 30 times 1998's. The penguins, hit twice, stayed below half their pre-1982 number. | NOAA closed the California sea lion mortality event at the end of September 2016. The longer-term effects are hard to separate from the "Blob". | Too early to say. Phytoplankton often rebounds after El Niño; after 1997–98 the La Niña brought a large eastern Pacific bloom. |
| Southern California | Very wet: 33.19 in at Downtown LA (234% of normal). January–March 1983 storms destroyed a third to half of the Santa Monica Pier, and mudslides closed Pacific Coast Highway. | Very wet: 30.57 in (215%). December 1997 mudflows ran through Laguna Beach; warm water emptied the squid grounds. | Dry: 6.88 in (48%) despite the record ONI. The ocean effects (starving sea lion pups, toxic algae) were bigger than the rain. | Winter rain has not started. Sea level at Los Angeles has run about 1 ft above the tide tables since 13 Oct (Kelvin wave plus marine heatwave). Rain outlook: see the PDO card below. |
Rain: Downtown LA water year (Oct–Sep), % of the 1991–2020 normal of 14.2 in (RCC-ACIS). Marine-life sources: Glynn et al. 2018, Marine Pollution Bulletin 133 (Galápagos corals); Valle et al. 1987, Condor 89 (1982–83 penguins and cormorants); Vargas et al. 2006, Biological Conservation (penguins 1997–98 and 2004); Wilkinson (ed.), Status of Coral Reefs of the World: 2000; CalCOFI Reports 40 and 41 (squid catches 1998–99); NOAA Fisheries (2013–16 sea lion mortality event; 2014–16 marine heatwave); Hughes et al. 2018, Nature (Great Barrier Reef); NASA PACE (Aug 2026); NOAA Coral Reef Watch (Galápagos station). Santa Monica Pier: Santa Monica Daily Press. 2026 sea level: NOAA CO-OPS Los Angeles.
Chance (%) of each ENSO category for each 3-month target season. Rows are matched by target season, not by position; "—" means that source has no forecast for that season. Each value is a seasonal probability, not monthly odds. Issued: CPC — · IRI —.
CPC official: consensus of NOAA CPC forecasters (with IRI), verified against the relative Niño 3.4 index (RONI); categories are ±0.5 °C, and the "≥ +1.5 °C" column is the chance of a strong or very strong El Niño. CPC also puts the chance of a historic event (RONI ≥ +2.5 °C) at 83% for Oct–Dec. IRI objective: computed by regression from the model plume below, with no forecaster judgement, using the traditional Niño 3.4 anomaly (OISST, 1991–2020). The two use different indices, so differences of a few points are expected. Sources: CPC strength probabilities, CPC ENSO discussion, IRI ENSO forecast.
Issued by NOAA CPC on —, for the target seasons listed. Unconditional probabilities: each value is the chance of that strength out of all outcomes, not the chance given that El Niño occurs. The four strengths add up to CPC's El Niño probability, and the grey remainder (Neutral or La Niña) brings each bar to 100%. Strength uses the 3-month RONI: weak +0.5 to +1.0 °C, moderate +1.0 to +1.5, strong +1.5 to +2.0, very strong ≥ +2.0.
Source: Official NOAA CPC ENSO Strength Probabilities (numeric table). Percentages are CPC's own rounded values.
IRI/CCSR plume issued October 2026: 27 models (16 dynamical, 11 statistical). Thin lines are single models; the shaded band is their full range. These are temperature-anomaly forecasts, not probabilities: IRI uses them to compute its objective probabilities above, but the plume is not another set of official CPC probabilities. Values are traditional Niño 3.4 anomalies (OISST v2.1, 1991–2020 base), which run warmer than RONI.
* Observed: IRI's July–September and September values. Plume values are read from IRI's published figure geometry (the data tables are not public) and cross-checked so the mean of the single models reproduces IRI's plotted average to ±0.01 °C.
What the PDO is. The Pacific Decadal Oscillation describes the North Pacific's slow temperature pattern. In its positive phase the water along North America is warm and the central North Pacific cool; in its negative phase the reverse. It shifts over years to decades, while ENSO shifts over months. In September 2026 the PDO was −1.55, strongly negative. Among El Niño winters since 1951, only 2023–24 had a lower PDO. In 1982, 1997 and 2015 it was positive (+0.5, +1.8, +1.0).
Why it could matter. El Niño's heat in the tropics strengthens the subtropical jet stream and deepens the Aleutian Low in the Gulf of Alaska. That steers storms into California. A positive PDO works in the same direction. A negative PDO pushes the other way: it favours high pressure over the northeast Pacific, the blocking "ridge" that diverts storms north to Canada and leaves California dry. So the two patterns are pulling in opposite directions this winter.
What history actually shows. The record is more reassuring than the theory. In Downtown Los Angeles, all four El Niño winters with a negative PDO were wetter than normal, including 2023–24 (PDO −1.7, rain 156% of normal). The two driest strong El Niño winters, 2015–16 (48%) and 1986–87 (40%), both had a positive PDO. The PDO sign alone has not decided Los Angeles rainfall.
Why it is still the wild card. No winter on record combines an El Niño this strong (ONI above +2) with a PDO this negative, so there is no true analogue. Ten winters are too few to rule anything out. And the September PNA was −0.64, the opposite of the usual El Niño pattern. A North Pacific ridge has not yet given way to the deep Aleutian Low that brings storms south.
Status from NOAA's California Current Marine Heatwave Tracker (update of 30 Sep 2026, still the latest as of 23 Oct) and NOAA's C-COAST assessment (25 Sep 2026); PDO from NOAA NCEI (ERSSTv5). Reviewed every Friday. Marine heatwave = sea-surface temperature above the 90th percentile for the date, sustained over a large area.
| 2014–16 "Blob" | Now (Oct 2026) | |
|---|---|---|
| Size | Basin-scale; NOAA calls it unique in its record. It persisted until mid-2016. | Two separate heatwaves, neither described by NOAA as Blob-sized. |
| How long | More than 700 continuous days of high temperatures in the California Current (back-to-back events, 2014–16). | About 17 months: the California heatwave (NOAA's NEP25A) has been tracked since May 2025. |
| Southern California | Warm water from 2014 onward. | Heatwave affecting central and southern California, expanding and intensifying in recent weeks; NOAA says late-September warming may be partly El Niño-driven. Santa Monica Bay buoy: about 74°F on 25 Aug, nearly 6°F above its 26-year average for the date; 47 daily records there in 2026 (Scripps CDIP, via Surfer, 2 Sep). |
| Washington to N. California | Warm along the whole coast. | Average to slightly above; only small, short-lived patches. |
| Gulf of Alaska | The Blob's core, built under a ridge that persisted through the 2013–14 and 2014–15 winters. | Offshore heatwave (NEP26A) since May 2026, growing in area and intensity, not yet reaching the coast. Little stored subsurface heat, since winter 2025–26 brought no major warm anomalies there (NOAA PSL). |
| Steering pattern | Persistent ridge off the West Coast for months. | Not persistent: ridge 5–8 Oct, trough 10–11 Oct (500 hPa, ridge watch on this dashboard). |
| PDO (Sep) | +0.76 (2014), +0.97 (2015) | −1.55, the opposite sign |
| Outlook | — | NOAA: 80–100% chance of marine heatwave conditions off California through the end of 2026, 30–70% off Oregon and Washington. The concern is how long the heat lasts rather than further intensification. |
| Wildlife | Mass die-offs: about 62,000 common murre carcasses washed ashore and more than half of Alaska's roughly 8 million murres disappeared (the toll may have reached 1 million birds); thousands of starving sea lion pups stranded. | No similar widespread die-off documented as of early July 2026 (Desert Sun, citing NOAA). |
| El Niño | Arrived in 2015 on top of the Blob, then peaked at ONI +2.6. | Already near-record (JAS ONI +2.16), with Kelvin waves raising LA sea level about 1 ft. |
Sources: NOAA IEA California Current Marine Heatwave Tracker; NOAA IEA C-COAST (25 Sep 2026); Surfer (2 Sep 2026, Scripps CDIP buoys); Desert Sun via AOL (6 Jul 2026, murre and sea lion figures from NOAA); NOAA PSL, "Severity and persistence of Northeast Pacific marine heatwaves vary by season" (Jul 2026); Bond et al. 2015, Geophysical Research Letters 42 (causes of the 2014 warm anomaly); NOAA NCEI PDO; The Inertia (3 Oct 2025, citing NOAA, on the 2025 heatwave).
OISST v2.1 weekly anomalies, 1991–2020 base. The dashed line marks the highest weekly Niño 3.4 value before 2026.
3-month centred mean of CPC's standardized Tahiti minus Darwin SOI, in CPC units (multiply by 10 for the BOM scale). Negative values are El Niño-like.
Monthly sea-surface temperature anomaly, °C vs 1991–2020 (NOAA ERSSTv5, box means), and the ONI. Aligned so the El Niño years line up: 2015 with 2026, so the x-axis starts in January 2013 and January 2024.
The Blob box is the region Bond et al. (2015) used for the 2014 warm anomaly. Months not yet published are left blank.
San Fernando Valley, Los Angeles (Burbank area). Free public feeds read on 11 October 2026 at about 11:00 PDT: NWS api.weather.gov (forecast, alerts, Burbank airport observations), Open-Meteo (hourly forecast and air quality), NOAA CO-OPS Santa Monica tide station, NASA FIRMS fire detections, CAL FIRE incidents, and the downtown Los Angeles rainfall record from RCC-ACIS. Times are Pacific.
Point forecast from the NWS Los Angeles/Oxnard office (grid LOX 150,51), issued 16 Oct 2026, 1:07 pm PDT. In effect when read: Red Flag Warning until 8 pm Sat 17 Oct and Wind Advisory until 2 pm Sat.
| Period | Forecast | °F | Rain chance % | Wind |
|---|
Open-Meteo model forecast, °F, from two days ago to seven days ahead. A widening gap between the two lines means drying air.
Relative humidity (%) and wind gusts (mph). Low humidity with rising northeasterly gusts after rain is the classic Santa Ana set-up; follow NWS Red Flag Warnings for official fire-weather alerts.
Open-Meteo precipitation probability (%).
US AQI and fine particles (PM2.5, µg/m³), Open-Meteo/CAMS model. Dashed lines at AQI 50 (good to moderate) and 100 (unhealthy for sensitive groups). For official readings use South Coast AQMD or AirNow.
NWS station KBUR, about 6 km from the San Fernando Valley, last 36 hours. Temperature and dew point, °F.
NOAA station 9410840, feet above mean lower low water. The gap between the observed and predicted lines is water the tide table does not explain: storm surge, wind and the raised sea level that comes with El Niño's warm water.
| Time (PDT) | High or low | Predicted ft |
|---|
— possible fire detections within 100 km in the past 5 days · — from persistent industrial heat sources
NASA FIRMS VIIRS detections (Suomi NPP and NOAA-20), past 5 days (the most the FIRMS API returns). Spots that show up night after night at the same place with low power are landfills, refineries and power plants, not wildfires, and are drawn hollow. Rings at 25, 50 and 100 km. Satellite detections are unconfirmed; CAL FIRE's list below is the official incident record.
| CAL FIRE active incident | County | Started | Acres | Contained % |
|---|
CDEC daily storage: the ten largest reservoirs plus Southern California's Pyramid, Castaic and Lake Perris. "% of average" compares with the historical average for this date; above 100 means fuller than usual going into the wet season.
| Reservoir | % full | % of average for the date | Storage (acre-feet) | Capacity (acre-feet) |
|---|
El Niño median — in · neutral — in · La Niña — in · 1991–2020 normal — in
Downtown Los Angeles, October–September totals, 1951–2025, coloured by the winter's ONI (DJF). The record goes back to 1877; this chart starts where the ONI does. Strong El Niño winters have been wet in all but one case (2015–16).
Snapshot of USGS, Smithsonian GVP, NHC and GDACS feeds taken on 11 October 2026 between 17:25 and 19:00 UTC. Maps are Pacific-centred; hover a symbol for details.
Everything in one view: M4.5+ earthquakes of the past 7 days (USGS), volcanoes active this week (Smithsonian GVP, USGS alerts, GDACS), hurricanes and typhoons with tracks (NHC, GDACS/JTWC), current floods, wildfires and drought flagged by GDACS, and NASA FIRMS satellite fire detections from the past 24 hours (1° cells, sized by total fire radiative power). Select a layer to show or hide it.
| Type | Event | Where | When (UTC) | Alert |
|---|
USGS, magnitude 4.5 and above, past 30 days. Circle size follows magnitude; colour shows depth.
| Time (UTC) | Mag | Location | Depth km | PAGER |
|---|
Smithsonian/USGS Weekly Volcanic Activity Report for 1–7 October 2026 (published 8 October), with current USGS alert levels for US volcanoes (ringed). The weekly report covers volcanoes with notable activity that week, not every eruption under way.
| Volcano | Country | Activity | Report summary |
|---|
| US volcano | Observatory | Alert level | Aviation code | Latest notice |
|---|
Positions and tracks from NHC (Atlantic and eastern Pacific) and GDACS/JTWC (western Pacific and other basins). Solid lines are the past track, dashed lines the official forecast; colour shows the strength along the track.
| Storm | Basin | Status | Wind kt | Pressure mb | Peak kt | Movement | As of (UTC) |
|---|
The whole planet's vital signs, read monthly from the project data sheet: NASA GISTEMP v4 global temperature, NOAA Mauna Loa CO₂ and the Rutgers Northern Hemisphere snow cover record.
NASA GISTEMP v4 land–ocean anomaly vs 1951–1980, °C. Grey band: the warmest and coolest value for each month in 1991–2022.
Annual mean anomaly vs 1951–1980, °C. 2026 is January–September.
Monthly mean (seasonal saw-tooth) and the de-seasonalised trend, ppm, NOAA GML.
Monthly land snow cover minus the 1991–2020 average for that month, million km², Rutgers Global Snow Lab, since 2015.
Explore how scientists reconstruct past climates from natural archives and archaeological evidence, and what those records can tell us about environmental change. Every chart states what was measured, what is reconstructed from it, the reference period, the resolution and the uncertainty. Ancient reconstructions and modern observations are kept apart.
Pick a time window. Each window uses the published records that resolve it best, so the archives, units and reference periods change from one window to the next. They are not spliced together, and none is joined to modern thermometer data.
The thin line is the ensemble median for each year; the bold line and band are the 31-year filtered median and 95% range published with the data, which is the scale the authors recommend for interpretation. The filter cannot be computed for the first and last 15 years, so the bold line starts in 16 CE and stops in 1985. Values are relative to 1961–1990, a different reference from the 12,000-year view (1800–1900). Proxy coverage thins before about 1000 CE, which is why the band widens toward the left. The reconstruction ends in 2000.
Time runs in years BP (before 1950 CE), the convention of the source data. Each point is the median of a 100-year bin plotted at its centre: 0 BP covers 1900–2000 CE, 100 BP covers 1800–1900. The shaded band is where 90% of the ensemble falls, combining proxy, dating and method uncertainty. Values are relative to 1800–1900, so zero is the 19th century. The latitude bands rest on far fewer records than the global mean, which is why their bands are wider. The record stops in the 20th century: it is not joined to today's thermometer readings, which are shown separately under Modern context. Instrumental figures use a different reference (1850–1900 or 1951–1980) and annual rather than centennial resolution.
Five separate published records on one shared time axis (thousands of years before 1950). Ice-core gases stop at 1750 CE (0.2 ka) so the industrial rise stays in Modern context. Each has its own archive, age model and units; small offsets in timing between panels partly reflect different age scales. Hover any panel for values.
Temperature, CO₂ and methane rise and fall together through each glacial cycle; sea level follows with the growth and melt of ice sheets. Ice-core temperature is local to central Antarctica, where glacial–interglacial swings are roughly twice the global mean. The ice-core gases are direct measurements of ancient air; the temperature and sea-level curves are reconstructions. Sea level carries a 1σ uncertainty of 9–12 m according to its authors, so the stack's value of about +9 m at 0 ka is within error of zero rather than a real offset. The cave record mainly tracks the strength of the summer monsoon and Northern Hemisphere summer sunshine (the 23,000-year precession cycle), so its rhythm is faster than the ice-age cycle. None of these panels includes post-industrial measurements; those are under Modern context.
Benthic δ18O mixes two signals: how much water is locked in land ice, and how cold the deep ocean is. Both move the same way, so higher values mean a colder, icier world. The long drift toward higher values is the cooling from the warm Pliocene into the ice ages. The cycles grow larger and longer: about 41,000 years before roughly 1.2 million years ago, then about 100,000 years after the Mid-Pleistocene Transition (MPT, shaded, about 1.2–0.8 Ma). The age model is tuned to orbital cycles, so its timing is not independent of them.
The same measurement as the 5.3-million-year view, extended across the whole Cenozoic by splicing deep-sea cores. Before about 34 million years ago there were no large ice sheets, so δ18O mainly reflects deep-ocean temperature; after that it also records ice volume. Marked events: the Paleocene–Eocene Thermal Maximum (about 56 Ma), the Eocene–Oligocene transition when Antarctica's ice sheet formed (about 34 Ma), and the onset of large Northern Hemisphere ice sheets (about 2.7 Ma). Fifty-thousand-year medians hide short events: the PETM lasted under 200,000 years and appears here as a spike only a few bins wide.
Each explainer answers the same five questions. Archaeological material and natural archives are labelled separately, even when a study uses both.
Rain and food water → body water → enamel growing day by day → isotope measurement → inferred rainfall pattern
Example: Smith et al. 2024, orangutan teeth.
Growing-season weather → ring width, wood density, isotopes → cross-dated to the exact year → calibrated against instrumental records → inferred temperature or drought
Archive: NOAA's International Tree-Ring Data Bank, more than 5,000 sites on six continents.
Snowfall and air → buried and compressed into layered ice with trapped bubbles → isotopes, gases, dust and sulphate measured → inferred local temperature, greenhouse gases, volcanism
Example: Jouzel et al. 2007, EPICA Dome C.
Thermometer and air-sampling records, measured rather than reconstructed, with their own reference periods and annual or monthly resolution. Not joined to the reconstructions above.
For scale: ice cores show CO₂ stayed between about 170 and 300 ppm for the 800,000 years before industrialisation (Lüthi et al. 2008, Nature); today's level is outside that range.
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Looking down on the North Pole, to 55°N. Circles show today's mean temperature minus the 1991–2020 normal for the date (Open-Meteo/ERA5); red is warmer, blue colder.
Looking down on the South Pole, to 55°S. Same comparison with the 1991–2020 normal.
Model analysis at each point (Open-Meteo), °C, with the 1991–2020 ERA5 normal for 8–14 October. Grid-point values, not the stations' own thermometers.
| Place | Region | Now °C | Today's mean °C | Normal °C | Anomaly °C | Wind km/h |
|---|
NSIDC Sea Ice Index, 5-day mean, million km². Shading spans the 10th–90th percentile of 1981–2010; dashed line is the median.
Same measures for the Southern Ocean. 2023 holds most of the record lows.
Lowest Arctic extent and highest Antarctic extent of each year, 5-day mean. 2026 Antarctic maximum is the season to date.
Daily ozone hole area (NASA Ozone Watch, million km²) against the 1979–2025 range: shading spans the 10th–90th percentile, dashed line is the mean.
Mean area 7 September–13 October, NASA. 2026 covers 7 September–8 October so far. No data for 1995. 1979 is the first full year of satellite measurements and serves as the pre-hole baseline; the hole was first reported in 1985 (British Antarctic Survey, Halley).
Annual mean temperature as a difference from each station's 1981–2010 average (ERA5 reanalysis at the station location, via Open-Meteo). Before 1979 there were no satellite data to constrain the model, so early values are less reliable, especially inland.
1979: an ordinary year at the coast (Halley −0.2 °C, Faraday −0.8 °C vs average) but cold inland: Vostok −1.8 °C, its 3rd-coldest year since 1958, with a cold winter (May −4.6, July −5.2 °C). Since 1977: South Pole and Vostok average about 1.4–1.6 °C warmer than 1958–76, Faraday 1.0 °C; Halley shows little change.
CPC monthly indices since 2020. Positive values mean the polar vortex is strong and cold air stays near the pole; negative values let it spill toward mid-latitudes.
Every tropical cyclone active since 25 September, with 6-hourly positions coloured by Saffir–Simpson category (IBTrACS provisional best tracks, plus the latest NHC advisory). Press play or drag the slider: earthquakes of M5 and above appear at the moment they struck and fade over two days, and GDACS flood and volcano alerts appear on their start dates. At the latest time, dashed lines show the official forecast tracks.
Damage and casualty reports from news and civil-protection sources, as of the time shown. Early counts usually rise; follow the linked source for updates.
| Storm | Basin | Category | Wind kt | Pressure mb | Fix (UTC) |
|---|
Each extreme event answered the same way: the setup weeks ahead, the trigger, the amplifiers that made it extreme, and the climate signal from a formal attribution study where one exists. Click an event's name for its full deep-dive in the Event log: how it developed, what steered it and how it ended, with sources.
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Pearson r (bar), Spearman rank correlation, effective sample size after allowing for year-to-year persistence, and a block-permutation p-value. With twelve tests, a link counts as robust only when p is below 0.05 ÷ 12 ≈ 0.004.
| Relationship | Pearson r | Spearman | Effective N | p (permutation) | Verdict |
|---|
r = — · permutation p = —
Each dot is one season, 1950–2025. ONI for August–October against Atlantic accumulated cyclone energy (ACE, 10⁴ kt²). El Niño years sit low.
r = — · permutation p = —
ONI for August–October against western Pacific ACE (JTWC best tracks via IBTrACS), 1950–2024. The strongest link in the set.
r = — · permutation p = —
ONI for August–October against eastern and central Pacific ACE (NHC HURDAT2), 1950–2025.
r = — · permutation p = —
Annual-mean ONI against the number of M6+ mainshocks per year (USGS catalogue, aftershocks removed with Gardner–Knopoff windows).
r = — · permutation p = —
Annual-mean ONI against confirmed eruption starts per year (Smithsonian GVP), with the long-term reporting trend removed.
r = — · permutation p = —
M6+ mainshocks against eruption starts, year by year, both with their long-term trend removed.
Average M6+ mainshocks and eruption starts per month during El Niño (ONI ≥ +0.5), neutral and La Niña (ONI ≤ −0.5) months, 1950–2026. Near-identical bars mean no ENSO effect.
Correlation between monthly ONI and later (positive lag) or earlier (negative lag) monthly mainshock and eruption counts. Dashed lines show the rough 95% band for chance; with 49 lags, two or three crossings are expected by chance alone.
Average ONI from 12 months before to 36 months after the start of 41 tropical eruptions of VEI 4 or more (1950–2024), against the 95% range of 5,000 sets of random dates. The shaded band is what chance alone produces.
OISST v2.1 weekly, 1991–2020 base, since January 2025. Relative anomalies subtract the tropical-mean anomaly, which removes the background warming of the whole tropics.
Monthly OISST anomaly difference, last 18 months. A widening gap means the warmth is concentrated in the far eastern Pacific, the signature of an east-based event.
One region, four monthly measures since 2025. The spread between them is why every quoted figure needs its dataset and method.
OISST v2.1 monthly anomaly, 1991–2020 base. Dashed lines at ±0.5 °C, the usual El Niño and La Niña thresholds.
Upper-300 m temperature anomaly, 180°–100°W (CPC, °C vs 1981–2010), and warm water volume anomaly (PMEL, ×10¹⁴ m³), since 1979. Subsurface heat leads the surface by 1–3 months; dashed line marks the 1997 heat-content record (+2.56 °C).
Accumulated cyclone energy by basin (Colorado State real-time, season to date) against the normal for the date. A record-strength El Niño boosts the eastern and western Pacific and suppresses the Atlantic.
| Basin | ACE | Normal | Named storms | Normal | Hurricanes | Major |
|---|
Monthly OISST anomalies since 2023: North Atlantic (5–20°N, 60–30°W), South Atlantic (0–20°S, 30°W–10°E) and the global tropics (10°S–10°N).
Bars: monthly standardized SOI (CPC). Line: 3-month centred mean. Dotted line: Equatorial SOI (standardized eastern Pacific minus Indonesia sea-level pressure).
Monthly sea-level pressure anomaly, hPa, since January 2026. High pressure at Darwin means suppressed convection over northern Australia and the Maritime Continent.
Standardized monthly indices, since 2025. Negative values are weaker easterly trades: West (135°E–180°), Central (175°W–140°W), East (135°W–120°W).
Monthly OLR anomaly, 170°E–140°W, 5°S–5°N, 1991–2020 base, W/m², since 2015. Negative values mean more deep convection.
Monthly zonal wind anomaly at the equator, m/s, since 2015 (CDAS). Negative values, upper-level easterly anomalies, are typical of El Niño.
PDO (monthly, NOAA NCEI ERSSTv5, via the project data sheet) and AMO (NOAA NCEI ERSSTv5, North Atlantic 0–60°N, linear trend removed, to Sep 2026; Sep 2026 = +0.59 °C, record +0.82 in mid-2023), both as 12-month running means, since 1950. Cross-check: our OISST calculation, North Atlantic minus the 60°S–60°N global ocean (NCAR method), was +0.24 °C on 27 Sep 2026 — also warm, lower because the record El Niño is warming the global mean. Warm PDO phases favour El Niño and a wetter US Southwest; a warm AMO favours busy Atlantic hurricane seasons and Sahel rain.
Dipole Mode Index, °C, since 2015: NOAA CPC (ERSSTv6, to Aug 2026) with the older PSL HadISST series (dashed, stops May 2026). Cross-check: our OISST calculation was +0.90 °C on 27 Sep 2026 (west +1.34, east +0.44). Above +0.4: positive IOD, dry for Australia and Indonesia, wet for East Africa. Below −0.4: the reverse.
CPC monthly anomaly (5.5–23.5°N, 15–57.5°W), °C, since 2015. This is the hurricane main development region, the tropical part of the AMO.
CPC monthly standardised indices since 2020. Positive NAO: mild, wet, stormy northern Europe and a mild eastern US; negative NAO: cold northern Europe and a stormier Mediterranean. Positive PNA: ridge over western North America, cold East; negative PNA often brings a wetter Pacific Northwest and a drier Southwest.
Real-time OMI (NOAA PSL, CPC OLR) in RMM-style phase space. Inside the circle the MJO is weak. Phases 1–3: rain over Africa and the Indian Ocean; 4–5: Maritime Continent; 6–7: western Pacific (favours West Coast storms and Atlantic quiet); 8: Western Hemisphere.
Daily mean 500 mb height difference from normal (metres), past 7 days and 16-day forecast (Open-Meteo blend). Above +100 m: a ridge that steers storms away; below −100 m: a trough that opens the storm door. A ridge over the Gulf of Alaska with a trough off California is the classic pattern for Southern California storms. Normal = 2021–2025 average for the same dates (short baseline).
Daily maximum total column water vapour (mm) from the Open-Meteo forecast blend, past 7 days and next 16. Values above about 20 mm over coastal California usually mean an atmospheric river; 30 mm or more is a strong one. This is a moisture proxy, not CW3E's official AR scale.
Zonal-mean zonal wind at 30 mb and 50 mb (CDAS), m/s, since 2015. Positive values are the westerly phase, which is associated with weaker boreal-winter MJO activity.
Monthly anomaly, °C (CDAS), since 1979. This series carries long-term warming as well as ENSO, so read it as background, not as an ENSO index.
Space weather, the polar vortex, Greenland, the coast and Earth's rotation, read from the project data sheet (NOAA SWPC, SILSO, CPC, GFS via Open-Meteo, NOAA CO-OPS, Coral Reef Watch, NOAA LSA, IERS). Times on the coast charts are Pacific.
Daily maximum planetary Kp (NOAA SWPC). 5 = G1 minor storm, 6 = G2, 7 = G3 strong, 8 = G4, 9 = G5. Highlighted bars are storm days.
F10.7 solar radio flux (sfu) and the SWPC daily sunspot number. Both track how active the Sun is; flux above about 150 means a very active Sun.
Monthly sunspot number (SILSO, Royal Observatory of Belgium) and its 13-month smoothed mean. Cycle 25 peaked at about 161 in October 2024 and is now declining toward a minimum around 2030.
The South Atlantic Anomaly is growing. Over the South Atlantic, southeast of South America, the magnetic field is weaker than anywhere else. Eleven years of ESA Swarm satellite data show the weak area has grown since 2014 by roughly half the size of continental Europe, and southwest of Africa the field has weakened even faster since 2020. Over the same period the field strengthened over Siberia and weakened over Canada. The cause lies at the top of Earth's liquid core: "reverse flux patches" where the field points back into the core instead of out of it.
Why it matters. A weaker field lets more radiation reach satellites as they pass over the region, which can cause glitches, hardware damage and blackouts. ESA mentions no effect on weather or climate.
The deep "blobs". About 3,000 km down, just above the core, two continent-sized masses of hot rock sit beneath Africa and the Pacific (geologists call them large low-shear-velocity provinces, because seismic waves slow down inside them). Biggin et al. (2026) found they are hotter than the surrounding mantle and draw less heat out of the core, which has shaped the magnetic field for at least the last few hundred million years. They move millimetres per year: nothing about them changes on a human timescale, and they have no link to the ocean "Blob" or El Niño.
Sources: ESA, "Swarm reveals growing weak spot in Earth's magnetic field" (13 Oct 2025); Biggin, A. J. et al., "Mantle heterogeneity influenced Earth's ancient magnetic field", Nature Geoscience 19, 345–352 (2026), published online 3 Feb 2026; University of Liverpool summary (4 Feb 2026).
Zonal wind at 60°N and 10 hPa (about 30 km up), averaged over eight longitudes from GFS, m/s; dashed = forecast. Normal for late October is roughly 15–30 m/s and rising. A drop below 0 (winds reversing) is a sudden stratospheric warming, which often sends Arctic air south 2–6 weeks later.
CPC daily AO index since July. Positive = cold air locked near the pole; negative = cold air spills into the mid-latitudes.
Daily maximum air temperature at five points on the ice sheet (Open-Meteo), °C. Above 0 °C means surface melt. A proxy for NSIDC's melt extent, which is not available in a form the sheet can import.
NOAA CO-OPS station 9410660 (Los Angeles), feet above MLLW. The gap between the two lines is what the tide tables miss: the marine heatwave and El Niño Kelvin waves.
Sea-level pressure at LAX minus Tonopah, Nevada (hPa), with the LAX humidity. Below −6 hPa is a real Santa Ana; −10 or lower is strong. Past and forecast hours, Open-Meteo.
Degree heating weeks (°C-weeks), NOAA Coral Reef Watch 5 km virtual stations. 4 or more: bleaching likely; 8 or more: severe bleaching likely; 12 or more: coral deaths likely.
| Reef | Date | SST °C | Hotspot °C | Heat stress now | Alert | 2026 peak | Peak date |
|---|
Satellite altimetry (NOAA Laboratory for Satellite Altimetry), mm, seasonal cycle removed. Trend about 3.1 mm a year and speeding up. The source file currently ends in February 2025.
Monthly mean polar motion (IERS), arcseconds; 0.1″ ≈ 3 m on the ground. The big loops are the Chandler wobble plus the yearly wobble. The loops shrank after 2010 as the Chandler wobble faded.
Bars: Chandler wobble amplitude in a 6-year window centred on each year (milliarcseconds, fitted to IERS polar motion). Line: M7+ mainshocks per year (USGS, aftershocks removed with Gardner–Knopoff windows). The wobble faded from about 190 mas in the early 1990s to under 20 in 2016–22 — a real and unusual change — but quake counts did not follow it.
7,042 M6+ mainshocks sorted into eight Moon phases. The dashed line is what an even spread would give. If tides triggered large quakes, the New and Full bars would stand out.
p = chance of a result this strong with no real link (Rayleigh test for Moon phase; phase-randomised surrogates for the yearly series). Below 0.05 would be worth a closer look.
| Test | Quakes / years | Result | p | Verdict |
|---|
Verdict so far: across 192 tests of planetary cycles against eight climate indices (1950–2026), 10 came out “significant” at p < 0.05 — exactly what chance alone produces — and none survive a false-discovery-rate correction. Four leads keep the same sign in both halves of the record and are worth watching forward: Saturn–Neptune closeness vs ENSO, Saturn–Neptune hard aspects vs global temperature wiggles, Jupiter–Pluto hard aspects vs the PDO, and the 18.6-year lunar node cycle vs the PDO (the only one with a known physical mechanism, tidal mixing).
Geocentric positions on 13 October 2026, tropical zodiac, PyEphem. ℞ = retrograde.
| Body | Sign | Degree | Retrograde |
|---|
Sign ingresses and exact aspects between Jupiter, Saturn, Uranus, Neptune and Pluto. The Saturn–Neptune conjunction of 21 February 2026 at 0° Aries came during the build-up of the record El Niño.
| Date | Event | Type |
|---|
Angular separation of Jupiter–Saturn (≈20-year cycle) and Saturn–Neptune (≈36-year cycle), degrees (0 = conjunction, 180 = opposition), with the ONI drawn as 90 + ONI×60 so it fits the same axis (90 = neutral; hover shows the real ONI). With only two Saturn–Neptune cycles in the record, any match is very weakly tested.
r = correlation (±1 perfect, 0 none). p = chance of an r this large from a random index with the same persistence (2,000 surrogates). q = false-discovery rate across all 192 tests; below 0.10 would count as a real finding. “Replicates” = same sign and |r| ≥ 0.1 in 1950–87 and 1988–2026.
| Planetary predictor | Climate index | r | p | q | r 1950–87 | r 1988–2026 | Replicates |
|---|
Did large earthquakes or eruption onsets cluster around Mercury and Venus inferior conjunctions (Sun–planet–Earth in line), retrograde periods, double conjunctions like March 2025 and October–November 2026, Sun–Mercury–Venus–Earth line-ups, or five-planet clusters? Hazards: USGS M6+, M7+ and M7.5+ mainshocks (aftershocks removed; 5,207 / 658 / 214) and Smithsonian GVP eruption starts dated to the day (VEI 2+: 992; VEI 3+: 288). Expected = mean over 5,000 random time shifts of the hazard dates, which keeps their clustering. Result: no earthquake effect at all (ratios 0–1.3, every p ≥ 0.28; no M7.5+ quake fell within 15 days of any of the 7 double conjunctions or 9 line-ups, against 2.4 and 3.2 expected). Four of 65 tests reach p < 0.05 — chance alone gives about 3 — all for eruptions near Venus inferior conjunction; none survives the false-discovery correction (lowest q = 0.50), and the same test on 1900–1964 eruptions shows no excess (ratio 0.88–0.92, p > 0.6). It stays a forward test. Physics: at its closest, Venus raises a tide about 0.006% of the Moon's; Mercury's is about 0.00002%.
| Alignment | Window | Hazard | Observed | Expected | Ratio | p | q | Verdict |
|---|
Conjunctions with the Sun and retrograde stations (UTC day, PyEphem). The next double inferior conjunction: Venus 24 October and Mercury 4 November 2026. Base rate for judging any “hit”: the world averages about 13 M7+ mainshocks a year, so roughly two in three 31-day windows contain at least one.
| Date | Event | Type |
|---|
Predictors (monthly, 15th of each month): closeness (cosine of separation) and hard aspects (within 8° of 0°, 90° or 180°) for ten outer-planet pairs, heliocentric clustering of the planets, the number of retrograde planets, and the lunar node cycle. Indices: ONI, PDO, AMO, NAO, PNA, AO, AAO and global temperature with its long-term trend removed. Slow cycles and persistent climate indices produce chance correlations easily, so each p-value comes from surrogate indices with the same persistence, and the whole set is corrected for multiple testing. Forward test: these four leads are now fixed in advance and will be re-scored as new months arrive. Physical note: the planets' tidal pull on Earth is about a million times smaller than the Moon's, so a real effect would need an indirect route, for example through the Sun.
Papers used in the ENSO research pages. These carry Creative Commons licences that allow redistribution with credit, so a copy is kept on this site. Credit belongs to the authors and the original journals; the licence and source are given for each.
| Authors | Title and source | Licence | Used in | Copy |
|---|---|---|---|---|
| Chai, J., et al. (2020) | A robust equatorial Pacific westerly response to tropical volcanism in multiple models. Climate Dynamics 55, 3413–3429. doi:10.1007/s00382-020-05453-6 | CC BY 4.0 | 1982–83 paper: El Chichón | |
| Bell, B., et al. (2021) | The ERA5 global reanalysis: preliminary extension to 1950. Quarterly Journal of the Royal Meteorological Society 147, 4186–4227. doi:10.1002/qj.4174 | CC BY-NC-ND 4.0 | ERA5 checks (1982 bursts) | |
| Hersbach, H., et al. (2020) | The ERA5 global reanalysis. Quarterly Journal of the Royal Meteorological Society 146, 1999–2049. doi:10.1002/qj.3803 | CC BY 4.0 | ERA5 checks (1982 bursts) | |
| Khodri, M., et al. (2017) | Tropical explosive volcanic eruptions can trigger El Niño by cooling tropical Africa. Nature Communications 8, 778. doi:10.1038/s41467-017-00755-6 | CC BY 4.0 | 1982–83 paper: El Chichón | |
| Li, L., et al. (2023) | Comparison of Madden–Julian oscillation in three super El Niño events. Frontiers in Earth Science 10, 1021953. doi:10.3389/feart.2022.1021953 | CC BY | 1982–83 paper: MJO | |
| Prado, L. F., I. Wainer and P. L. da Silva Dias (2018) | Tropical Atlantic response to last millennium volcanic forcing. Atmosphere 9, 421. doi:10.3390/atmos9110421 | CC BY 4.0 | Background: volcanic forcing | |
| Liu, Q., X. Hao, C.-Z. Zou, L. Wang, J. J. Qu and B. Yan (2025) | A preliminary assessment of the VIIRS cloud top and base height environmental data record reprocessing. Remote Sensing 17, 1036. doi:10.3390/rs17061036 | CC BY 4.0 | Background: satellite cloud records | |
| Liu, S., B. Wu, C.-Z. Zou and Y. Wang (2023) | Highly consistent brightness temperature fundamental climate data record from SSM/I and SSMIS. IEEE Transactions on Geoscience and Remote Sensing 61, 5302313. doi:10.1109/TGRS.2023.3316694 | CC BY-NC-ND 4.0 | Background: satellite microwave climate records | |
| Predybaylo, E., et al. (2020) | El Niño/Southern Oscillation response to low-latitude volcanic eruptions depends on ocean pre-conditions and eruption timing. Communications Earth & Environment 1, 12. doi:10.1038/s43247-020-0013-y | CC BY 4.0 | 1982–83 paper: El Chichón | |
| Santer, B. D., et al. (2023) | Exceptional stratospheric contribution to human fingerprints on atmospheric temperature. Proceedings of the National Academy of Sciences 120(20), e2300758120. doi:10.1073/pnas.2300758120 | CC BY-NC-ND 4.0 | Background: satellite atmospheric temperature (NOAA STAR, used in Papers 1–4) | |
| Worsfold, M., et al. (2024) | Presenting a long-term, reprocessed dataset of global sea surface temperature produced using the OSTIA system. Remote Sensing 16, 3358. doi:10.3390/rs16183358 | CC BY | 1982–83 paper: El Chichón SST bias |
Of the 378 articles published in volume 39 so far (issues 1–22), 29 carry a Creative Commons licence on the final version or on a preprint or repository copy (Crossref and OpenAlex records, read 24 October 2026). 7 are kept on this site as the openly licensed preprint or repository version; the final, typeset versions are © American Meteorological Society unless marked CC BY. 16 final versions are CC BY 4.0 and free on the AMS site; copies will be added here once downloaded. For 6, the open licence of the final version still needs checking. Credit belongs to the authors and the journal.
| Authors | Title and source | Licence and version | Copy |
|---|---|---|---|
| Gilmour, Harriet; Chadwick, Robin; Catto, Jennifer L. et al. | Mesoscale Convective Systems over South America: Representation in Kilometer-Scale Met Office Unified Model Climate Simulations. Journal of Climate 39(1). doi:10.1175/jcli-d-24-0754.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Chadwick, Robin; Good, Peter; Garcia-Franco, Jorge L. et al. | Processes Controlling the South American Monsoon Response to Climate Change. Journal of Climate 39(1). doi:10.1175/jcli-d-25-0012.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Tian, Zhiping; Jiang, Dabang; Shi, Jiawen | Global Patterns of Increasing Interannual Variability of Surface Air Temperature throughout the Holocene. Journal of Climate 39(1). doi:10.1175/jcli-d-25-0117.1 | Listed as open access (CC BY); licence of the final version to be confirmed | Publisher |
| Sinclair, Mark R. | A Global Climatology of Tropical Cyclone Diabatic Rossby Wave Sources and Their Extratropical Flow Response. Journal of Climate 39(2). doi:10.1175/jcli-d-25-0175.1 | Listed as open access (CC BY-NC-ND); licence of the final version to be confirmed | Publisher |
| Guarino, Maria-Vittoria; Ridley, Jeff K.; Colwell, Steve et al. | A Long-Term Shift in Flow Regimes over the Antarctic Peninsula. Journal of Climate 39(2). doi:10.1175/jcli-d-25-0330.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Deoras, Akshay; Turner, Andrew G.; Volonté, Ambrogio et al. | The Role of Dry Intrusions in Breaks of the Indian Summer Monsoon. Journal of Climate 39(5). doi:10.1175/jcli-d-25-0004.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Wills, Robert C. J.; Deser, Clara; McKinnon, Karen A. et al. | Forced Component Estimation Statistical Method Intercomparison Project (ForceSMIP). Journal of Climate 39(8). doi:10.1175/jcli-d-25-0326.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Sun, Lantao; Wills, Robert C. J.; Deser, Clara et al. | Increased Model Resolution Amplifies Boreal Winter Arctic Precipitation and Atmospheric Circulation Response to Sea Ice Loss. Journal of Climate 39(9). doi:10.1175/jcli-d-25-0260.1 | Listed as open access (CC BY); licence of the final version to be confirmed | Publisher |
| Schnyder, Franziska; Riboldi, Jacopo | Linking Upstream Cold, Continental Air to the Intensity of Marine Cold-Air Outbreaks along the Western Boundary Currents of the North Pacific and North Atlantic: A Lagrangian Analysis. Journal of Climate 39(9). doi:10.1175/jcli-d-25-0336.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Strommen, Kristian; Michel, Simon L. L.; Christensen, Hannah M. | Corrigendum. Journal of Climate 39(10). doi:10.1175/jcli-d-25-0547.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Stewart, Kial Douglas; Schmaltz, Thomas Gregory; Shakespeare, Callum James | Dynamical Consequences of Polar Amplification on Standing Rossby Waves: A Laboratory Perspective. Journal of Climate 39(10). doi:10.1175/jcli-d-25-0583.1 | CC BY-NC-ND (preprint / repository version, arXiv (Cornell University) | PDF · final version |
| Vicente-Serrano, Sergio M.; Domínguez-Castro, Fernando; Beguería, Santiago et al. | Comments on “Mediterranean Drying by a Positive North Atlantic Oscillation Trend over the Last 65 Years Is an Extreme Outlier in the CMIP6 Multimodel Ensemble”. Journal of Climate 39(10). doi:10.1175/jcli-d-26-0055.1 | CC BY-NC (preprint / repository version, Zaguan (Universidad de Zaragoza) | PDF · final version |
| Baker, Alexander J.; Lockwood, Julia F.; Athanasiadis, Panos J. et al. | Reduced Future North Atlantic Eddy-Driven Jet Variability in High-Resolution, Fully Coupled Global Climate Models. Journal of Climate 39(11). doi:10.1175/jcli-d-25-0418.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Walsh, Amber; Screen, James A.; Scaife, Adam A. et al. | Interdependent Extratropical Atmospheric Responses to Arctic Sea Ice Loss, QBO, and ENSO. Journal of Climate 39(12). doi:10.1175/jcli-d-24-0518.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Jiang, Feng; Seager, Richard; Cane, Mark A. | Deus Ex Machina Long-Term Cooling of the Eastern Pacific Cold Tongue in Ocean Reanalysis Data. Journal of Climate 39(12). doi:10.1175/jcli-d-25-0356.1 | CC BY (preprint / repository version, Research Square) | PDF · final version |
| Kang, Joonsuk M.; Shaw, Tiffany A.; Sun, Lantao | Using Energetic Frameworks to Assess Artificial Heating in Coupled Model Sea Ice Loss Experiments. Journal of Climate 39(13). doi:10.1175/jcli-d-25-0746.1 | Listed as open access (CC BY-NC-ND); licence of the final version to be confirmed | Publisher |
| Linke, Olivia; Lenhardt, Julien; Lund, Marianne T. et al. | Understanding the Spread in Climate Feedbacks and Polar Amplification Using Coordinated Multimodel Experiments and CMIP6. Journal of Climate 39(14). doi:10.1175/jcli-d-25-0551.1 | Listed as open access (CC BY); licence of the final version to be confirmed | Publisher |
| Fredericks, Leif; Rugenstein, Maria; Thompson, David W. J. et al. | Quantifying the Radiative Response to Surface Temperature Variability: A Critical Comparison of Current Methods. Journal of Climate 39(14). doi:10.1175/jcli-d-25-0612.1 | CC BY-NC-SA (preprint / repository version, arXiv (Cornell University) | PDF · final version |
| Iwakiri, Tomoki; Kohyama, Tsubasa | Episodic Slowdown of Global Warming by a Multiyear La Niña. Journal of Climate 39(14). doi:10.1175/jcli-d-25-0686.1 | CC BY (preprint / repository version, preprint server) | PDF · final version |
| Suitters, Charlie C.; Screen, James A.; Catto, Jennifer L. et al. | Assessing the Likelihood of Unprecedented Antarctic Heat in the Current Climate. Journal of Climate 39(15). doi:10.1175/jcli-d-25-0436.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Taylor, Katherine L.; Evans, Michael N.; Schurer, Andrew P. et al. | Assessing the Ability of Tree-Ring-Derived Aridity Records to Detect Compound Drought and Heatwave Events. Journal of Climate 39(15). doi:10.1175/jcli-d-25-0472.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Spuler, Fiona R.; Kretschmer, Marlene; Balmaseda, Magdalena Alonso et al. | Disentangling Regional Impacts of Joint Teleconnections Using Causal Representation Learning. Journal of Climate 39(17). doi:10.1175/jcli-d-25-0700.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Geoffroy, Olivier; Saint-Martin, David | Global Kilometer-Scale Simulations with ARP-GEM2: Effect of Parameterized Convection and Calibration. Journal of Climate 39(18). doi:10.1175/jcli-d-25-0650.1 | CC BY (preprint / repository version, arXiv (Cornell University) | PDF · final version |
| Dong, Zeyao; Washington, Richard | Convectively Coupled Kelvin Waves over the Congo Basin: Modulation by Land Characteristics. Journal of Climate 39(18). doi:10.1175/jcli-d-26-0115.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Sahu, Limonlisa; Senapati, Balaji; Dash, Mihir K. et al. | Horseshoe Salinity Pattern in the Upper Indian Ocean and Its Decadal Variability. Journal of Climate 39(19). doi:10.1175/jcli-d-25-0730.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Sugiura, Togo; Takahashi, Hiroshi G. | Seasonal Variations in the MJO Propagation and Decay over the Maritime Continent owing to Background Circulation and Modulation by ENSO. Journal of Climate 39(19). doi:10.1175/jcli-d-26-0144.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Schulz, Marius A.; Hohenegger, Cathy | The Response of Tropical Land–Ocean Precipitation Partitioning to SST and CO2 Increase in Global Storm-Resolving Simulations. Journal of Climate 39(20). doi:10.1175/jcli-d-26-0041.1 | Listed as open access (CC BY); licence of the final version to be confirmed | Publisher |
| Megann, Alex; Copsey, Dan; Walsh, Amber | The Sensitivity of a Coupled Climate Model to Numerical Mixing in Its Ocean Component. Journal of Climate 39(21). doi:10.1175/jcli-d-25-0661.1 | CC BY 4.0 (final published version) | Publisher (free) |
| Kinsella, Alex; Mahadevan, Amala | A New Diagnostic of Air–Sea Interaction Reveals Ocean Control of Turbulent Heat Flux in the South Asian Summer Monsoon. Journal of Climate 39(21). doi:10.1175/jcli-d-26-0118.1 | CC BY (preprint / repository version, preprint server) | PDF · final version |
Annual update of the key indicators of the climate system and human influence, following IPCC AR6 methods: greenhouse-gas emissions and concentrations, effective radiative forcing, Earth energy imbalance, observed and human-induced warming, remaining carbon budget, land temperature and precipitation extremes, marine heatwaves and sea level. 31 CSV files, as downloaded on 23 October 2026. Licence: CC BY 4.0 (dataset record and paper). Cite: Forster, P. M., et al. (2026), Indicators of Global Climate Change 2025, Earth System Science Data 18, 3889–3933, doi:10.5194/essd-18-3889-2026; data: Smith, C., et al. (2026), doi:10.5281/zenodo.20499280. "Synthesis" files are the IGCC assessed values; the others are the input datasets or individual methods behind them.
These papers were read for the research pages but are under publisher copyright, so this site links to the publisher instead of posting the PDF.
| Authors | Title and source | Rights | Used in | Link |
|---|---|---|---|---|
| Bergman, J. W., H. H. Hendon and K. M. Weickmann (2001) | Intraseasonal air–sea interactions at the onset of El Niño. Journal of Climate 14, 1702–1719. | © American Meteorological Society | 1982–83 paper: MJO | Publisher search |
| Gutzler, D. S., and D. E. Harrison (1987) | The structure and evolution of seasonal wind anomalies over the near-equatorial eastern Indian and western Pacific Oceans. Monthly Weather Review 115, 169–192. | © American Meteorological Society | 1982–83 paper: Indian–Pacific | Publisher page |
| Harrison, D. E., and P. S. Schopf (1984) | Kelvin-wave-induced anomalous advection and the onset of surface warming in El Niño events. Monthly Weather Review 112, 923–933. | © American Meteorological Society | 1982–83 paper: Kelvin waves | Publisher page |
| Rasmusson, E. M., and T. H. Carpenter (1982) | Variations in tropical sea surface temperature and surface wind fields associated with the Southern Oscillation/El Niño. Monthly Weather Review 110, 354–384. | © American Meteorological Society | 1982–83 paper: pre-1982 composite | Publisher page |
| Weickmann, K. M., and S. J. S. Khalsa (1990) | The shift of convection from the Indian Ocean to the western Pacific Ocean during a 30–60 day oscillation. Monthly Weather Review 118, 964–978. | © American Meteorological Society | 1982–83 paper: Dec 1981 MJO | Publisher page |
| Bergman, J., H. Hendon and K. Weickmann (2001) | MJOs and the onset of ENSO (Research Spotlight on 1997–98). NOAA Physical Sciences Laboratory. | NOAA web page | 1982–83 paper: MJO background | NOAA page |
| Keen, R. A. (1982) | The role of cross-equatorial tropical cyclone pairs in the Southern Oscillation. Monthly Weather Review 110, 1405–1416. | © American Meteorological Society | 1982–83 paper: cyclone pairs | Publisher page |
| Roundy, P. E., and G. N. Kiladis (2007) | Analysis of a reconstructed oceanic Kelvin wave dynamic height dataset for the period 1974–2005. Journal of Climate 20, 4341–4355. | © American Meteorological Society | 1982–83 paper: MJO and Kelvin waves | Publisher page |
| Roundy, P. E., and G. N. Kiladis (2007) | Roles of the MJO in the development of oceanic Kelvin waves and ENSO (extended abstract 5B.4, 87th AMS Annual Meeting). AMS conference preprint. | © American Meteorological Society (free on AMS site) | 1982–83 paper: MJO | Publisher page |
| Schreck, C. J., and J. Molinari (2009) | A case study of an outbreak of twin tropical cyclones. Monthly Weather Review 137, 863–875. | © American Meteorological Society | 1982–83 paper: cyclone pairs | Publisher page |
| Zambri, B., A. N. LeGrande, A. Robock and J. Slawinska (2017) | Northern Hemisphere winter warming and summer monsoon reduction after volcanic eruptions. Journal of Geophysical Research: Atmospheres 122, 7971–7989. | © Wiley / American Geophysical Union | Background: volcanic forcing | Publisher page |
| Zuo, M., W. Man, T. Zhou and Z. Guo (2018) | Different impacts of northern, tropical, and southern volcanic eruptions on the tropical Pacific SST in the last millennium. Journal of Climate 31, 6729–6744. | © American Meteorological Society | 1982–83 paper: El Chichón | Publisher page |
| Lengaigne, M., et al. (2003) | The March 1997 westerly wind event and the onset of the 1997/98 El Niño: understanding the role of the atmospheric response. Journal of Climate 16, 3330–3343. | © American Meteorological Society | 1997–98 paper: westerly wind events | Publisher (DOI) |
| van Oldenborgh, G. J. (2000) | What caused the onset of the 1997–98 El Niño? Monthly Weather Review 128, 2601–2607 (preprint: arXiv:physics/9904002). | © American Meteorological Society (journal version); arXiv preprint | 1997–98 paper: onset decomposition | Publisher (DOI) |
| Picaut, J., et al. (2002) | Mechanisms of the 1997–1998 El Niño–La Niña, as inferred from space-based observations. Journal of Geophysical Research 107(C5), 3037. | © American Geophysical Union | 1997–98 paper: onset and termination | Publisher (DOI) |
| Ueda, H., and J. Matsumoto (2000) | A possible triggering process of east–west asymmetric anomalies over the Indian Ocean in relation to 1997/98 El Niño. Journal of the Meteorological Society of Japan 78, 803–818. | © Meteorological Society of Japan | 1997–98 paper: Indian Ocean | Publisher (DOI) |
| Barnston, A. G., et al. (1999) | NCEP forecasts of the El Niño of 1997–98 and its U.S. impacts. Bulletin of the American Meteorological Society 80, 1829–1852. | © American Meteorological Society | 1997–98 paper: forecasts | Publisher (DOI) |
| Landsea, C. W., and J. A. Knaff (2000) | How much skill was there in forecasting the very strong 1997–98 El Niño? Bulletin of the American Meteorological Society 81, 2107–2119. | © American Meteorological Society | 1997–98 paper: forecasts | Publisher (DOI) |
| Kessler, W. S., and R. Kleeman (2000) | Rectification of the Madden–Julian oscillation into the ENSO cycle. Journal of Climate 13, 3560–3575. | © American Meteorological Society | 1997–98 paper: MJO | Publisher (DOI) |
| Vecchi, G. A., and D. E. Harrison (2006) | The termination of the 1997–98 El Niño. Part I: Mechanisms of oceanic change. Journal of Climate 19, 2633–2646. | © American Meteorological Society | 1997–98 paper: termination | Publisher (DOI) |
| Vecchi, G. A. (2006) | The termination of the 1997–98 El Niño. Part II: Mechanisms of atmospheric change. Journal of Climate 19, 2647–2664. | © American Meteorological Society | 1997–98 paper: termination | Publisher (DOI) |
| McPhaden, M. J. (1999) | Genesis and evolution of the 1997–98 El Niño. Science 283, 950–954 (free author copy at NOAA PMEL). | © AAAS | 1997–98 paper: overview, termination | Publisher (DOI) |
| McPhaden, M. J., and X. Yu (1999) | Equatorial waves and the 1997–98 El Niño. Geophysical Research Letters 26, 2961–2964. | © American Geophysical Union | 1997–98 paper: Kelvin waves | Publisher (DOI) |
| Yu, L., and M. M. Rienecker (1998) | Evidence of an extratropical atmospheric influence during the onset of the 1997–98 El Niño. Geophysical Research Letters 25, 3537–3540. | © American Geophysical Union | 1997–98 paper: westerly bursts, cold surges | Publisher (DOI) |
| Kutsuwada, K., and M. McPhaden (2002) | Intraseasonal variations in the upper equatorial Pacific Ocean prior to and during the 1997–98 El Niño. Journal of Physical Oceanography 32, 1133–1149. | © American Meteorological Society | 1997–98 paper: Kelvin waves | Publisher (DOI) |
| Zhu, C., T. Nakazawa and J. Li (2003) | Modulation of twin tropical cyclogenesis by the MJO westerly wind burst during the onset period of 1997/98 ENSO. Advances in Atmospheric Sciences 20, 882–898. | © Springer / Science Press | 1997–98 paper: twin cyclones | Publisher (DOI) |
| Webster, P. J., A. M. Moore, J. P. Loschnigg and R. R. Leben (1999) | Coupled ocean–atmosphere dynamics in the Indian Ocean during 1997–98. Nature 401, 356–360. | © Macmillan / Springer Nature | 1997–98 paper: Indian Ocean | Publisher (DOI) |
| Zhang, B., B. J. Soden, G. A. Vecchi and W. Yang (2026) | Enhanced efficacy contributes to tropical cyclone intensification in warmer climates via stronger storm-scale radiative feedbacks. Journal of Climate 39(22), 6389–6399. | © American Meteorological Society (no open copy found, 24 Oct 2026) | 2026 storm papers: background on intensification in a warmer climate | Publisher (DOI) |
| Qin, L., and M. Konda (2026) | Physical processes to cause the seasonal change of the sea surface temperature in the equatorial Atlantic. Journal of Climate 39(22), 6401–6418. | © American Meteorological Society (no open copy found, 24 Oct 2026) | Background: equatorial Atlantic SST | Publisher (DOI) |
| Li, W.-H., and G. Li (2026) | Effect of spring Tibetan Plateau snow cover on the frequency of intense tropical cyclones over the western North Pacific. Journal of Climate 39(22), 6419–6436. | © American Meteorological Society (no open copy found, 24 Oct 2026) | 2026 typhoon papers: background on intense-typhoon frequency | Publisher (DOI) |
| Zhuo, L., B. E. J. Rose, P. E. Roundy and B. Zhang (2026) | How regional SST shapes Saharan near-surface temperature: sensitivity and dynamical mechanisms. Journal of Climate 39(22), 6437–6452. | © American Meteorological Society (no open copy found, 24 Oct 2026) | Background: SST teleconnections | Publisher (DOI) |
| Kanno, Y., A. Yamamoto, S. Ito and P. Martineau (2026) | Wintertime marine cold air outbreaks over the Northwest Pacific: Lagrangian climatology and downstream impacts. Journal of Climate 39(22), 6453–6469. | © American Meteorological Society (no open copy found, 24 Oct 2026) | Background: Northwest Pacific air–sea interaction | Publisher (DOI) |
| Shankle, M. G., et al. (2026) | Isolated Northern Hemisphere cooling in an idealized model promotes ocean carbon storage and glacial-like ocean features. Journal of Climate 39(22), 6471–6488. | © American Meteorological Society (no open copy found, 24 Oct 2026) | Background: paleoclimate | Publisher (DOI) |
Working guide to climate projections on the Copernicus Climate Data Store (CDS). Compiled by Claude on 23 October 2026 from the C3S training notebooks on global (CMIP6) and regional (CORDEX) projections, the C3S webinars on regional projections and in-situ data, and standard practice. It sets the rules this site follows before any projection appears on it. Projections are model output: they are never presented as observations or forecasts.
CMIP6 global projections (CDS: projections-cmip6). The historical experiment (1850–2014) and the SSP scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP5-8.5 and others) for 2015–2100, daily or monthly, on single and pressure levels. Models use different grids, so each model is requested separately. Files arrive as NetCDF inside a zip archive.
CORDEX regional projections (CDS: projections-cordex-domains-single-levels). Regional climate models (0.11°–0.44°) for 14 domains, each driven by a global model. Experiments: evaluation (driven by the ERA-Interim reanalysis, 1979–2015), historical, and the scenarios RCP2.6, RCP4.5 and RCP8.5. Files come in five-year blocks. The CORDEX runs on the CDS are driven by the earlier CMIP5 generation.
Not projections: seasonal forecasts (months ahead) and reanalyses such as ERA5 (the past). The interactive C3S Atlas, which also underlies the IPCC AR6 Atlas, gives quick pre-computed regional changes.
Through the CDS programming interface (cdsapi) or ECMWF's earthkit-data, run in GitHub Actions with the site's CDS account. Each dataset's licence must first be accepted on its CDS page: ERA5 and CMIP6 are accepted; CORDEX is still needed for regional work. Requests are kept small, one model and experiment at a time, as the C3S tutorials do. Processing uses the ECMWF earthkit suite (version 1.0.0): earthkit-data to read, earthkit-transforms for averages and climatologies, earthkit-plots for maps.
CMIP6 tutorial: downloads monthly near-surface temperature from seven models for the historical period and three scenarios, averages it globally with latitude weights, converts it to yearly °C and plots the median with the 10th–90th percentile range. It uses only seven light models for speed, and plots absolute temperatures; this site follows rule 2 and uses many more models.
CORDEX tutorial: one regional model over Africa (CanRCM4 driven by CanESM2), monthly climatologies for 1971–2000 and 2071–2100 under RCP4.5, and the difference between them (the delta method). One model is not an ensemble, and its plotting shortcut works only because the Africa domain is not rotated.
1. Global warming by scenario. CMIP6 global annual temperature as anomalies from 1850–1900 under SSP1-2.6, SSP2-4.5 and SSP5-8.5, with the model spread, checked against the observed NASA GISTEMP record on the Planet tab. Licence accepted; next to run.
2. Southern California. CORDEX North America change in Los Angeles temperature and rainfall (delta method against 1991–2020 observations). Needs the CORDEX licence.
Every WeatherWatch research paper and report in one place: the four El Niño papers, the 2026 hurricane and typhoon papers and the climate reports. Drafts are labelled in each paper; a PDF copy is listed where one exists.
| Date | Title | Type | Page |
|---|
Episodes follow NOAA's working definition: at least five overlapping 3-month seasons with ONI at or above +0.5 °C (El Niño) or at or below −0.5 °C (La Niña). Several records start in 1979 or 1982, so their charts begin there.
Seasonal Niño 3.4 index, ERSSTv6, from 1950. RONI subtracts the tropical-mean anomaly. Dashed lines at ±0.5 °C.
CPC standardized Tahiti minus Darwin, 3-month centred mean, and Equatorial SOI (5-month centred mean for readability), from 1951.
Monthly anomaly, centred base periods, from 1950. The longest monthly record of the region.
Monthly OISST anomalies, 1991–2020 base, from 1982. The far east and the western edge of the Niño regions.
Monthly sea-level pressure anomaly, hPa, 12-month trailing mean, from 1951.
Standardized 850 mb index, 175°W–140°W, 3-month centred mean, from 1979. Negative values are weaker trades.
Monthly anomaly, W/m², 1991–2020 base, from 1979. Negative values mean more deep convection.
Monthly zonal wind anomaly, m/s, 3-month centred mean, from 1979.
Monthly OISST anomalies, 12-month trailing mean, from 1982.
From the ONI. Strength labels use the common informal convention (peak ONI 0.5–0.9 weak, 1.0–1.4 moderate, 1.5–1.9 strong, 2.0 and above very strong); they are not an official NOAA classification. An episode still under way is listed as ongoing even before it reaches five seasons. Select a column heading to sort.
All series come from the project data sheet "Weather Watch_NOAA source data", which mirrors NOAA CPC index files. The sheet was read on 11 October 2026; the dashboard holds that snapshot until it is refreshed.
| Series | Sheet tab | CPC file | Base and period |
|---|---|---|---|
| Weekly Niño regions, absolute and relative | SST, RSST | wksst9120.for, rel_wksst9120.txt | OISST v2.1, 1991–2020, weekly (centred on Wednesday) |
| Monthly Niño regions, absolute and relative | SST, RSST | sstoi.indices, rel_mthsst9120.txt | OISST v2.1, 1991–2020, monthly |
| ONI and RONI | SST, RSST | oni.ascii.txt, RONI.ascii.txt | ERSSTv6, centred base periods (ONI) and 1991–2020 (RONI), 3-month |
| Monthly ERSST Niño 3.4, absolute and relative | SST, RSST | detrend.nino34.ascii.txt, Rnino34.ascii.txt | ERSSTv6, monthly |
| Atlantic and global tropics | SST | sstoi.atl.indices | OISST v2.1, 1991–2020, monthly |
| SOI and Equatorial SOI | SOI | soi, reqsoi.for | Standardized, CPC units, monthly |
| SOI 3-month mean | derived | soi (checked against soi.3m.txt) | Centred 3-month mean of monthly standardized SOI |
| Darwin and Tahiti pressure | SLP | darwin, tahiti | Anomaly, hPa, monthly |
| Trade winds, 200 mb wind, QBO | Winds | wpac850, cpac850, epac850, zwnd200, qbo.u30.index, qbo.u50.index | CDAS, monthly |
| OLR | OLR | cpolr.mth.91-20.ascii | 1991–2020, monthly |
| 500 mb temperature | Temperatures | z500t | CDAS, monthly anomaly |