The so-called hiatus in global annual average temperature between 2002 – 2014, once controversial to some but now well-established in the peer-reviewed literature, ended in 2014 with the start of a series of record-breaking El Nino events that spiked global temperature with a subsequent fall-back. Now a new study into the effect of man-made aerosol pollution adds to likely reasons for the end of the hiatus, and may point to lower estimates for future global warming.
An international research team writing in the journal Atmospheric Chemistry and Physics, uses satellite data to show that concentrations of aerosol particles have decreased significantly since 2000. This is good news as cleaner air benefits health, but it also reduces particles’ which have a cooling effect on the terrestrial climate.
According to the Intergovernmental Panel on Climate Change (IPCC), by 2019 the global temperature had risen by 1.1 degrees Celsius compared to pre-industrial levels due to increasing greenhouse gasses from burning fossil fuels. At the same time the combustion of fossil fuels emit aerosols which cool our climate by reflecting sunlight and increasing the reflectivity of clouds.
Professor Johannes Quaas, a meteorologist at Leipzig University, and colleagues from Europe, China, and the US have published robust observational evidence of significant reduction of aerosol pollution and improved global air quality.
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When taken together with a couple of super-strong El Nino events which temporarily drove up global temperature (see graph below), the new findings suggest that the global warming hiatus — clearly evident prior to 2014 — may not have ended yet. If NASA’s satellite data are confirmed, it would suggest that much of the very moderate changes in global temperature this century may have been driven primarily by cleaner air and naturally-occurring El Ninos.
Global temperature changes 2000-2022. Source: Met Office/HadCRUT5…
The climate pattern El Niño varies over time to such a degree that scientists will have difficulty detecting signs that it is getting stronger with global warming.
That’s the conclusion of a study led by scientists at The University of Texas at Austin that analyzed 9,000 years of Earth’s history. The scientists drew on climate data contained within ancient corals and used one of the world’s most powerful supercomputers to conduct their research.
The study of the past, which was recently published in Science Advances, was motivated by the need to get a clearer picture of how climate change may affect El Niño in the future.
El Niño is the warm phase of the El Niño Southern Oscillation, a climate phenomenon that sets the stage every few years for weather patterns worldwide. Strong El Niño events, such as the ones in 1997 and 2015 that brought wildfires to the rainforests of Borneo in Asia and caused widespread bleaching to the world’s coral reefs, happened about once a decade.
Computer models, however, are unclear about whether El Niño events will become weaker or stronger as the world warms due to climate change.
The climate pattern El Niño varies over time to such a degree that scientists will have difficulty detecting signs that it is getting stronger with global warming.
That’s the conclusion of a study led by scientists at The University of Texas at Austin that analyzed 9,000 years of Earth’s history. The scientists drew on climate data contained within ancient corals and used one of the world’s most powerful supercomputers to conduct their research.
The study of the past, which was recently published in Science Advances, was motivated by the need to get a clearer picture of how climate change may affect El Niño in the future.
El Niño is the warm phase of the El Niño Southern Oscillation, a climate phenomenon that sets the stage every few years for weather patterns worldwide. Strong El Niño events, such as the ones in 1997 and 2015 that brought wildfires to the rainforests of Borneo in Asia and caused widespread bleaching to the world’s coral reefs, happened about once a decade.
Computer models, however, are unclear about whether El Niño events will become weaker or stronger as the world warms due to climate change.
“Much of the world’s temperature and rainfall are influenced by what happens in the tropical Pacific Ocean where El Niño starts,” said the study’s lead author, Allison Lawman, who began the research as a Ph.D. project at the UT Jackson School of Geosciences and is now a postdoctoral researcher at the University of Colorado Boulder. “The difference in rainfall between greater or fewer strong El Niño events is going to be a critical question for infrastructure and resource planners.”
“The scientific community has been unclear on the role that solar variability plays in influencing weather and climate events here on Earth. This study shows there’s reason to believe it absolutely does and why the connection may have been missed in the past.”
Top: Six-month smoothed monthly sunspot number from SILSO. Bottom: Oceanic El Niño Index from NOAA. Red and blue boxes mark the El Niño and La Niña periods in the repeating pattern. Source: Climate Etc, September 2019
If you ask most climate scientists, they will tell you that the Sun’s small variability is unimportant when it comes to influencing climate. They may have to change their minds if a new line of research holds up. It seems that solar variability can drive climate variability on Earth on decadal timescales (the decadal climatic variability that Michael Mann recently ‘proved’ doesn’t exist). That’s the conclusion of a new study showing a correlation between the end of solar cycles and a switch from El Nino to La Nina conditions in the Pacific Ocean. It’s a result that could significantly improve the predictability of the largest El Nino and La Nina events, which have several global climate effects.
Many of you will be familiar with the work of Bob Tisdale over the years, concerning the mechanism of ENSO (ie El Ninos and La Ninas) and its effects on climate.
His seminal series of videos, recorded in 2012 is still on YouTube, and is still highly relevant.
Above is Part 1, which is worth sticking with all the way through, but otherwise the first 8 minutes is definitely worth a watch. Nothing has effectively changed since 2012, and Bob’s conclusions are still relevant and valid.
As well as explaining what exactly drives El Ninos and La Ninas, he makes some significant points:
Worldwide sea surface temperature trends since 1980 show no correlation with GHGs (see chart below)
Instead they exhibit a series of step changes up, which follow the major El Nino events of 1982/83, 1987/88 and 1997/98
Contrary to popular belief, global SSTs do not drop during La Nina episodes. This is because El Ninos transfer a vast amount of warm, subsurface water to the surface, where it remains during La Nina.
Some of this warm water in the East Pacific finds its way into the West Pacific and Indian Oceans. But through a process called teleconnection, SSTs is the Atlantic, where there is no direct connection, also rise and exhibit the same step changes.
Between major El Nino events, SSTs outside the East Pacific do not rise.
In the East Pacific, there has been no trend increase in SST at all since 1980.
2020 is gearing up to be another warm year, strongly affected by natural and regional weather events
It’s that time of the year again when some meteorological organisations predict what the average global temperature might be for the full, current year. Not that we have all the data for 2020, obviously, for most global temperature datasets haven’t even processed November’s data yet. Making a prediction with only just over 80% of the data available is a risky procedure and most sensible scientists would be very circumspect about doing so. But these premature annual announcements are done for political purposes and, in a typical year, always as a precursor to a UN climate conference.
2020 has been a warm year, one of the warmest – and warm years make many people throw caution to the wind, making claims based on select facts they like, ignoring the ones they don’t like.
Let’s go back a few years to the early part of this decade when global temperature had been stagnating for more than ten years and not increasing significantly, as many had predicted. But then came 2014-15 when they started rising again, peaking in 2016. Many voices proclaimed that this was evidence that global temperatures were now accelerating ‘out of control’, something their models had been predicting all along. The climate was making up for all the unchanging years of the so-called global warming hiatus, it was claimed.
Never mind that the sudden rise between 2015 and 2016 was occurring much faster than could be due to greenhouse forcing alone.
2010 – 2020: HadCrut4 global surface temperature change (green); Oceanic Niño Index (ONI) (red/blues)
However, it was not a coincidence that 2016 experienced a record El Nino. For some commentators, however, an El Nino is a finite event. According to its definition – a specific temperature increase in a certain region of the Pacific – an El Nino is either on or off. Hence, they said that subsequent warm years after 2016 were warm due to greenhouse forcing, not El Nino. They argued that average global temperature since then was not influenced by any El Nino warming.
But that’s clearly not the case. The build-up in temperatures before recent El Ninos is obviously not independent of its peak and neither is the decline afterwards, else why did that increase not continue after the El Nino’s ‘interruption.’ So, a year can still be showing the warming influence of previous El Nino conditions whilst not having an El Nino event, something many journalists and even the General Secretary of the World Meteorological Organisation (WMO), Prof Taalas, prefer to ignore.
Last year Germany’s Potsdam Institute (PIK) boasted that it had a superior El Niño one-year forecasting model, claiming 80% certainty. Today, a year later, its forecast emerges totally wrong and the prestigious institute is left humiliated.
In 2019, Germany’s Potsdam Climate Institute (PIK) boasted that it had a superior El Niño forecasting model, claiming one year in advance and with 80% certainty, there would be an El Niño event late in 2020 (upper curve is just an El Niño illustration). But the PIK model forecast flopped totally. The opposite has in fact emerged. Chart source: BOM (with additions).
One year ago, together with researchers of the Justus Liebig University Giessen (JLU), and Bar-Ilan University in Ramat Gan in Israel, Germany’s alarmist yet highly regarded Potsdam Institute for Climate Research (PIK) boldly declared in a press release there would “probably be another ‘El Niño’ by the end of 2020.”
As we can see, the period 1925 to 1945 was dominated by powerful El Ninos. This of course was also the time of great warming in the Arctic, known as “The Warming in The North”, when temperatures across much of the Arctic were as high as they are now.
During the 1950s, a much colder climate took over in the Arctic, until it became warmer again in the 90s. This was also a period when La Ninas dominated.
Coincidence?
The climate in the Arctic is also very well correlated with the Atlantic Multidecadal Oscillation (AMO):
HOUSTON – (March 26, 2020) – There is no longer a need to guess what ocean temperatures were like in the remote tropical Pacific hundreds of years ago. The ancient coral that lived there know all.
A study in Science led by Rice University and Georgia Tech researchers parses the record archived by ancient tropical Pacific coral over the past millennium. That record could help scientists refine their models of how changing conditions in the Pacific, particularly from volcanic eruptions, influence the occurrence of El Niño events, which are major drivers of global climate.
They found the ratio of oxygen isotopes sequestered in coral, an accurate measure of historic ocean temperatures, shows no correlation between estimates of sulfate particles ejected into the atmosphere by tropical volcanic eruptions and El Niño events.
That result could be of particular interest to scientists who suggest seeding the atmosphere with sun-blocking particles may help reverse global warming.
According to Rice climate scientist and primary author Sylvia Dee, previous climate model studies often tie volcanic eruptions, which increase sulfate aerosols in the atmosphere, to increased chances for an El Niño event. But the ability to analyze climate conditions based on oxygen isotopes trapped in fossil corals extends the climatological record in this key region across more than 20 ancient eruptions. Dee said this allows for a more rigorous test of the connection.
“A lot of climate modeling studies show a dynamical connection where volcanic eruptions can initiate El Niño events,” Dee said. “We can run climate models many centuries into the past, simulating volcanic eruptions for the last millennium.
“But the models are just that — models — and the coral record captures reality.”
Coral data that Georgia Tech climate scientist Kim Cobb and her team arduously collected on trips to the Pacific show little connection between known volcanoes and El Niño events over that time. Like tree rings, these paleoclimate archives hold chemical indicators, the oxygen isotopes, of oceanic conditions at the time they formed.
The coral data yields a high-fidelity record with a resolution of less than a month, tracking the El Niño-Southern Oscillation (ENSO) in the heart of the central tropical Pacific.
by Roy Spencer, January 15, 2020 in WUWT/Ch.Rotter
The increasing global ocean heat content (OHC) is often pointed to as the most quantitative way to monitor long-term changes in the global energy balance, which is believed to have been altered by anthropogenic greenhouse gas emissions. The challenge is that long-term temperature changes in the ocean below the top hundred meters or so become exceedingly small and difficult to measure. The newer network of Argo floats since the early 2000s has improved global coverage dramatically.
A new Cheng et al. (2020) paper describing record warm ocean temperatures in 2019 has been discussed by Willis Eschenbach who correctly reminds us that such “record setting” changes in the 0-2000 m ocean heat content (reported in Zettajoules, which is 10^^21 Joules) amount to exceedingly small temperature changes. I calculate from their data that 2019 was only 0.004 0.009 deg. C warmer than 2018.
Over the years I have frequently pointed out that the global energy imbalance (less than 1 W/m2) corresponding to such small rates of warming is much smaller than the accuracy with which we know the natural energy flows (1 part in 300 or so), which means Mother Nature could be responsible for the warming and we wouldn’t even know it.
The Cheng (2017) dataset of 0-2000m ocean heat content changes extends the OHC record back to 1940 (with little global coverage) and now up through 2019. The methodology of that dataset uses optimum interpolation techniques to intelligently extend the geographic coverage of limited data. I’m not going to critique that methodology here, and I agree with those who argue creating data where it does not exist is not the same as having real data. Instead I want to answer the question:
If we take the 1940-2019 global OHC data (as well as observed sea surface temperature data) at face value, and assume all of the warming trend was human-caused, what does it imply regarding equilibrium climate sensitivity (ECS)?
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Fig. 1. Deep-ocean temperature variations 1940-2019 explained with a 2-layer energy budget model forced with RCP6 radiative forcing scenario and a model climate sensitivity of 1.85 deg. C. The model also matches the 1940-2019 and 1979-2019 observed sea surface temperature trends to about 0.01 C/decade. If ENSO effects are not included in the model, the ECS is reduced to 1.7 deg. C.
The continuing global-average warmth over the last year has caused a few people to ask for my opinion regarding potential explanations. So, I updated the 1D energy budget model I described a couple years ago here with the most recent Multivariate ENSO Index (MEIv2) data. The model is initialized in the year 1765, has two ocean layers, and is forced with the RCP6 radiative forcing scenario and the history of El Nino and La Nina activity since the late 1800s.
The result shows that the global-average (60N-60S) ocean sea surface temperature (SST) data in recent months are well explained as a reflection of continuing weak El Nino conditions, on top of a long-term warming trend.
Fig. 1. 1D model of global ocean temperatures compared to observations. The model is forced with the RCP6 radiative forcing scenario (increasing CO2, volcanoes, anthropogenic aerosols, etc.) and the observed history of El Nino and La Nina since the late 1800s. The observations are monthly running 3-month averages and are offset with a single bias to match the model temperatures, which are departures from assumed energy equilibrium in 1765.
A major uncertainty in figuring out how much of recent warming has been human-caused is knowing how much nature has caused. The IPCC is quite sure that nature is responsible for less than half of the warming since the mid-1900s, but politicians, activists, and various green energy pundits go even further, behaving as if warming is 100% human-caused.
The fact is we really don’t understand the causes of natural climate change on the time scale of an individual lifetime, although theories abound. For example, there is plenty of evidence that the Little Ice Age was real, and so some of the warming over the last 150 years (especially prior to 1940) was natural — but how much?
The answer makes as huge difference to energy policy. If global warming is only 50% as large as is predicted by the IPCC (which would make it only 20% of the problem portrayed by the media and politicians), then the immense cost of renewable energy can be avoided until we have new cost-competitive energy technologies.
The recently published paper Recent Global Warming as Confirmed by AIRSused 15 years of infrared satellite data to obtain a rather strong global surface warming trend of +0.24 C/decade. Objections have been made to that study by me (e.g. here) and others, not the least of which is the fact that the 2003-2017 period addressed had a record warm El Nino near the end (2015-16), which means the computed warming trend over that period is not entirely human-caused warming.
If we look at the warming over the 19-year period 2000-2018, we see the record El Nino event during 2015-16 (all monthly anomalies are relative to the 2001-2017 average seasonal cycle):
Ces deux dernières années ont été marquées par une activité cyclonique supérieure aux moyennes statistiques en Atlantique Nord, notamment en 2017 avec des phénomènes puissants tels Irma et Maria dans les Caraïbes. Cette année, alors que la saison démarre officiellement le 1er juin, nos prévisions sont plus rassurantes avec la perspective d’une activité cyclonique légèrement plus faible que la moyenne.
En ce début d’été météorologique, la saison cyclonique débute dans l’Atlantique nord (les ouragans). Cette saison s’étend officiellement du 1er juin au 30 novembre, avec un pic d’activité d’août à octobre. Il est donc l’heure pour les différents organismes météo de la planète et les météorologues et climatologues de La Chaîne Météo de se pencher sur les prévisions de cette saison à venir.
En 2017, la saison dans l’océan Atlantique nord a figuré parmi les plus actives depuis le début des relevés, avec des phénomènes dévastateurs (Harvey, Irma ou encore Maria dans les Caraïbes). Comme 2017, la saison 2018 s’est située au-dessus des moyennes (calculées par la NOAA d’après la période 1981/2010). Cette dernière saison a présenté, pour l’Atlantique nord, 15 phénomènes cycloniques, avec 8 ouragans dont 2 qui ont atteint la catégorie 3 sur 5, qualifiés alors de “majeurs”.
CFAN predicts an active North Atlantic hurricane season season.
The Atlantic hurricane has begun. We are off to an early start with one wimpy subtropical storm that lasted less than a day, and a small system that is trying to spin up in the Bay of Campeche.
Other forecast providers have begun issuing forecasts:
NOAA predicts a near normal season with 4-8 hurricanes.
Tropical Storm Risk predicts slightly below normal activity, with 6 hurricanes and ACE of 88.
El Nino and warmer-than-average Atlantic help shape this season’s intensity
From NOAA press release:
NOAA’s Climate Prediction Center is predicting that a near-normal Atlantic hurricane season is most likely this year. This outlook forecasts a 40% chance of a near-normal season, a 30% chance of an above-normal season and a 30% chance of a below-normal season. The hurricane season officially extends from June 1 to November 30.
For 2019, NOAA predicts a likely range of 9 to 15 named storms (winds of 39 mph or higher), of which 4 to 8 could become hurricanes (winds of 74 mph or higher), including 2 to 4 major hurricanes (category 3, 4 or 5; with winds of 111 mph or higher). NOAA provides these ranges with a 70% confidence. An average hurricane season produces 12 named storms, of which 6 become hurricanes, including 3 major hurricanes.
A major uncertainty in figuring out how much of recent warming has been human-caused is knowing how much nature has caused. The IPCC is quite sure that nature is responsible for less than half of the warming since the mid-1900s, but politicians, activists, and various green energy pundits go even further, behaving as if warming is 100% human-caused.
The fact is we really don’t understand the causes of natural climate change on the time scale of an individual lifetime, although theories abound. For example, there is plenty of evidence that the Little Ice Age was real, and so some of the warming over the last 150 years (especially prior to 1940) was natural — but how much?
The answer makes as huge difference to energy policy. If global warming is only 50% as large as is predicted by the IPCC (which would make it only 20% of the problem portrayed by the media and politicians), then the immense cost of renewable energy can be avoided until we have new cost-competitive energy technologies.
The recently published paper Recent Global Warming as Confirmed by AIRSused 15 years of infrared satellite data to obtain a rather strong global surface warming trend of +0.24 C/decade. Objections have been made to that study by me (e.g. here) and others, not the least of which is the fact that the 2003-2017 period addressed had a record warm El Nino near the end (2015-16), which means the computed warming trend over that period is not entirely human-caused warming.
If we look at the warming over the 19-year period 2000-2018, we see the record El Nino event during 2015-16 (all monthly anomalies are relative to the 2001-2017 average seasonal cycle):
Melbourne: Australian scientists have developed an innovative method using cores drilled from coral to produce a world first 400-year long seasonal record of El Niño events, a record that many in the field had described as impossible to extract.
The record published today in Nature Geoscience detects different types of El Niño and shows the nature of El Niño events has changed in recent decades.
This understanding of El Niño events is vital because they produce extreme weather across the globe with particularly profound effects on precipitation and temperature extremes in Australia, South East Asia and the Americas.
The 400-year record revealed a clear change in El Niño types, with an increase of Central Pacific El Niño activity in the late 20th Century and suggested future changes to the strength of Eastern Pacific El Niños.
“We are seeing more El Niños forming in the central Pacific Ocean in recent decades, which is unusual across the past 400 years,” said lead author Dr Mandy Freund.
“There are even some early hints that the much stronger Eastern Pacific El Niños, like those that occurred in 1997/98 and 2015/16 may be growing in intensity.”
This extraordinary result was teased out of information about past climate from coral cores spanning the Pacific Ocean, as part of Dr Freund’s PhD research at the University of Melbourne and the Centre of Excellence for Climate Extremes. It was made possible because coral cores – like tree rings – have centuries-long growth patterns and contain isotopes that can tell us a lot about the climate of the past. However, until now, they had not been used to detect the different types of El Niño events.
An El Niño that began to form last fall has matured and is now fully entrenched across the Pacific Ocean. Changes in sea surface temperatures (SSTs) brought about by an El Niño affect the atmosphere, resulting in distinctive changes in the rainfall pattern across the Pacific Basin. These changes show up as anomalies or deviations in NASA’s analysis of climatological rainfall.
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As with a traditional El Niño, the effects from a Central Pacific El Niño can still spread to the U.S. Also, clearly visible in the NASA-generated monthly average rainfall was an area of heavy rain over the southeast coast of Africa associated with the passage of Cyclone Idai, which devastated the region with torrential flooding.
CFAN’s 2019 ENSO forecast is for a transition away from El Niño conditions as the summer progresses. The forecast for Sept-Oct-Nov 2019 calls for 60% probability of ENSO neutral conditions, with 40% probability of weak El Niño conditions. – Forecast issued 3/25/19
Introduction
CFAN’s early season ENSO forecast is motivated by preparing our seasonal forecast for Atlantic hurricane activity. ENSO forecasts made in spring have traditionally had very low skill owing to the ENSO ‘spring predictability barrier.’
During fall 2018, there was warming in the Central Equatorial Pacific, leading to a weak El Niño Modoki pattern, which impacted the latter part of the Atlantic hurricane season. This transitioned to a weak (conventional) El Niño in February 2019 and the atmospheric anomalies became more consistent with a conventional El Niño pattern.
NOAA’s latest forecast: Weak El Niño conditions are likely to continue through the Northern Hemisphere spring 2019 (~80% chance) and summer (~60% chance).
CFAN’s ENSO forecast analysis is guided by the ECMWF SEAS5 seasonal forecast system and a newly developed statistical forecast scheme based on global climate dynamics analysis.
ENSO statistics
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Figure 1 illustrates the recent ENSO history as depicted by monthly Niño 3.4 anomalies from 1980 to February 2019.
NOAA gives a 55% chance of El Niño conditions persisting through the spring.
Sea surface temperatures in January — orange-red colors are above normal.
“While sea surface temperatures are above average, current observations and climate models indicate that this El Niño will be weak, meaning we do not expect significant global impacts through the remainder of winter and into the spring,” Halpert said.
It was a little more than 10 years ago that I published my first blog posts on the obvious upward steps in the sea surface temperatures of a large portion of the global oceans…upward steps that are caused by El Niño events…upward steps that lead to sunlight-fueled, naturally occurring global warming.
There is a very simple explanation for those El Niño-caused upward shifts that also make themselves known in the sea surface temperature data for much larger portion of the global oceans than I first presented a decade ago…the upward steps that are blatantly obvious in the satellite-era (starts November 1981) of sea surface temperature data for the South Atlantic, Indian and West Pacific Oceans, as shown in Figure 1, which together cover about 52% of the surfaces of the global oceans.
In late 2018, there were some predictions that there would be a significant El Niño event in 2019. There were strong hints of an El Niño event in both SST data and forecasts. In an April 6th 2018 essay, Bob Tisdale suggested “Looks like one may be forming right now.”
Wavelet analyses of modern global temperature anomalies provides an excellent visualization tool of temperature signal characteristics and patterns over the past 150 years. Scafetta recognized key temperature oscillations of about 9, 20 and 60-years using power spectra of global surface temperature anomalies. There has been much discussion about the 60-year quasi-oscillation both in WUWT and publications.
Detrending the temperature time series and removing the 60-year underlying trend enables insights into the interplay of interannual and decadal scales. Wavelet analyses reveals these periodic signals have distinguished patterns and characteristics that repeat over time suggesting natural external and internal influences. Interannual wavelet patterns that consist of 9-year and 3 to 5-year quasi-oscillations are repeated and dominate over 70% of the instrumental record. The 3 to 5-year discontinuous breakouts are coincident to El Niño and La Niña events of the El Niño-Southern Oscillation (ENSO). A period of quiescence from 1925 to 1960 is devoid of most wavelet signals suggesting different or transitional climate processes.
The fast approaching solar minimum and its potential impact on the upcoming winter season
By Meteorologist Paul Dorian
Overview
In the long term, the sun is the main driver of all weather and climate and multi-decadal trends in solar activity can have major impacts on oceanic and atmospheric temperatures. In addition, empirical observations have shown that the sun can have important ramifications on weather and climate on shorter time scales including those associated with the average solar cycle of around 11-years. For example, there is evidence that low solar activity during solar minimum years tend to be well-correlated with more frequent “high-latitude blocking” events compared to normal and this type of atmospheric phenomenon can play an important role in the winter season.
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his plot shows the daily observations of the number of sunspots during the last four solar cycles back to 1 January 1977 according to Solar Influences Data Analysis Center (SIDC). The thin blue line indicates the daily sunspot number, while the dark blue line indicates the running annual average. The current low sunspot activity is indicated by the arrow at the lower right of the plot. Last day shown: 30 Sep 2018. Data source: climate4you.com.
La géologie, une science plus que passionnante … et diverse
