by Dr A. Ollila, March 16, 2020 in ClimateChange Dispatch
During the years 2000-2014, the global temperature hardly increased, and that period has been called the temperature pause or hiatus.
The debate among the climate community has resulted in more than 200 research studies in some cases with opposite results about the reasons.
This amount of papers can be compared to the research studies of Earth’s energy balance and the greenhouse effect. I have found about 10 publications for both subjects.
During the years 2000-2014, the emissions of carbon dioxide were 126 gigatons carbon (GtC) being 31% of the total emission after 1750, but the greenhouse (GH) gases were not able to increase the temperature.
According to the IPCC, the temperature increase should have been 0.4°C from 2000 to 2014 (Ref. 1).
It looks like that the pause ended to the super El Nino 2015-2016 because the temperature has been thereafter about 0.2 °C above-the-pause average.
Research study about the pause and the ENSO
The impulse for my research study came from a story figure on WUWT that showed shortwave (SW) radiation variations during the pause.
A curve showed increased values around El Nino 2015-16 and thereafter. I decided to find out what could be the impact of this finding on the temperatures.
In Fig. 1, I have depicted the total solar irradiance (TSI), SW radiation and LW radiation from 2000 onward. This data is available from the CERES databank maintained by NASA.
Fig.1. TSI, SW radiation and LW radiation trends normalized to the altitude of 20 kilometers.
by K. Richard, March 2, 2020 in NoTricksZone
Using NASA’s MERRA-2 radiation data, scientists find shortwave radiation (SW) has been rising since the 1980s. The SW increase has been larger and faster than longwave radiation (LW) changes during this same timespan. Cloud variability has been the “main driver” of these trends.
In a new Nature journal paper (Delgado-Bonal et al, 2020) published in Scientific Reports, scientists use radiation records from NASA to conclude shortwave (SW) changes are “mainly determined” by cloud modulation.
Clouds are “showing a declining trend” from 1984-2014. Fewer clouds means less SW radiation is reflected to space and more is absorbed by the Earth’s surface.
by James Murphy, January 16, 2020 in NewAmerican
With all of the pseudo-scientific propaganda being peddled about anthropogenic climate change, people sometimes forget that there are other, far more important drivers of the Earth’s climate than mankind’s carbon dioxide emissions. For example, that big ball of yellow light in the sky (aka the sun) has a huge effect on climate. And according to NASA, this year will mark the lowest level of solar activity in 200 years.
“Research now underway may have found a reliable new method to predict this solar activity. The Sun’s activity rises and falls in an 11-year cycle. The forecast for the next solar cycle says it will be the weakest of the last 200 years. The maximum of this next cycle — measured in terms of sunspot number, a standard measure of solar activity level — could be 30-50 percent lower than the most recent one. The results show that the next cycle will start in 2020 and reach its maximum in 2025.”
According to a growing number of scientists, the coming lower solar cycle — number 25 — may simply be a precursor to a period of prolonged solar minima such as the Maunder and Spörer minimums of the past millennium.
by Zharkova V. V. et al., June 24, 2019 in Nature OPEN ACCESS
Recently discovered long-term oscillations of the solar background magnetic field associated with double dynamo waves generated in inner and outer layers of the Sun indicate that the solar activity is heading in the next three decades (2019–2055) to a Modern grand minimum similar to Maunder one. On the other hand, a reconstruction of solar total irradiance suggests that since the Maunder minimum there is an increase in the cycle-averaged total solar irradiance (TSI) by a value of about 1–1.5 Wm−2 closely correlated with an increase of the baseline (average) terrestrial temperature. In order to understand these two opposite trends, we calculated the double dynamo summary curve of magnetic field variations backward one hundred thousand years allowing us to confirm strong oscillations of solar activity in regular (11 year) and recently reported grand (350–400 year) solar cycles caused by actions of the double solar dynamo. In addition, oscillations of the baseline (zero-line) of magnetic field with a period of 1950 ± 95 years (a super-grand cycle) are discovered by applying a running averaging filter to suppress large-scale oscillations of 11 year cycles. Latest minimum of the baseline oscillations is found to coincide with the grand solar minimum (the Maunder minimum) occurred before the current super-grand cycle start. Since then the baseline magnitude became slowly increasing towards its maximum at 2600 to be followed by its decrease and minimum at ~3700. These oscillations of the baseline solar magnetic field are found associated with a long-term solar inertial motion about the barycenter of the solar system and closely linked to an increase of solar irradiance and terrestrial temperature in the past two centuries. This trend is anticipated to continue in the next six centuries that can lead to a further natural increase of the terrestrial temperature by more than 2.5 °C by 2600.
by University of California – Santa Cruz, Oct 30, 2019 in ScienceDaily
As planetary systems evolve, gravitational interactions between planets can fling some of them into eccentric elliptical orbits around the host star, or even out of the system altogether. Smaller planets should be more susceptible to this gravitational scattering, yet many gas giant exoplanets have been observed with eccentric orbits very different from the roughly circular orbits of the planets in our own solar system.
Surprisingly, the planets with the highest masses tend to be those with the highest eccentricities, even though the inertia of a larger mass should make it harder to budge from its initial orbit. This counter-intuitive observation prompted astronomers at UC Santa Cruz to explore the evolution of planetary systems using computer simulations. Their results, reported in a paper published in Astrophysical Journal Letters, suggest a crucial role for a giant-impacts phase in the evolution of high-mass planetary systems, leading to collisional growth of multiple giant planets with close-in orbits.
by Cap Allon, October 7, 2019 in Electroverse
Bone chilling cold descended into Europe over the weekend, exactly as forecast by the GFS. And the ‘Polar Invasion’ will continue to seize practically ALL of the continent throughout the week, sinking temps as much as 20C below average, with only far Western regions spared.
This past Sunday went down as the coldest October 6th ever recorded in ALL of Holland, in record books dating back to 1901 (solar minimum of cycle 13).
The country’s daily high, measured at the national weather station in De Bilt, climbed to just 9.6C (49F), which busted the previous record low of 10.1C (50F) set back in 1936 (just exiting solar min of cycle 16).
The weekend’s chill was thanks to a descending Arctic air mass which brought icy easterly winds, thick cloud cover and heavy rain. This pattern will run for rest of the week, and is expected to see further record lows temps tumble.
While across Europe the story is the same, too — all-time cold records will likely tumble in Central, Southern and Eastern parts, particularly during the first half of the week, with Italy, the Ukraine, Romania, Greece, Hungary, Slovakia, Austria and southern Poland on course to be worst hit:
by K. Richard, October 3, 2019 in NoTricksZone
In the last few years, hundreds of peer-reviewed scientific papers have been published linking changes in solar activity to Earth’s climate (2016, 2017, 2018). The evidence for a robust Sun-Climate connection continues to accumulate in 2019.
When it comes to the Sun’s influence on climate, one conclusion is certain: there is no widespread scientific agreement as to how and to what extent solar activity and its related parameters (i.e., galactic cosmic rays, geomagnetic activity, solar wind flux) impact changes in the Earth’s temperature and precipitation.
The disagreement is so chasmic and the mechanisms are so poorly understood that scientists’ estimates of the influence of direct solar irradiance forcing between the 17th century and today can range between a negligible +0.1 W m-2 to a very robust +6 W m-2 (Egorova et al., 2018; Mazzarella and Scafetta, 2018).
“There is no consensus on the amplitude of the historical solar forcing. The estimated magnitude of the total solar irradiance difference between Maunder minimum and present time ranges from 0.1 to 6 W/m2 making uncertain the simulation of the past and future climate.” (Egorova et al., 2018)
“According to the IPCC (2013), solar forcing is extremely small and cannot induce the estimated 1.0–1.5 °C since the LIA. However, thesolar radiative forcing is quite uncertain because from 1700 to 2000 the proposed historical total solar irradiance reconstructions vary greatly from a minimum of 0.5 W/m2 to a maximum of about 6 W/m2 (cf..: Hoyt and Schatten 1993; Wang et al. 2005; Shapiro et al. 2011). Moreover, it is believed that the sun can influence the climate also via a magnetically induced cosmic ray flux modulation (e.g.: Kirkby 2007) or via heliospheric oscillation related to planetary resonances (e.g.: Scafetta 2013, 2014b; Scafetta et al. 2016, and others). Since solar and climate records correlate quite significantly throughout the Holocene (cf: Kerr 2001; Steinhilber et al. 2012; Scafetta 2012, 20104b), the results shown herein may be quite realistic, although the exact physical mechanisms linking astronomical forcings to climate change are still poorly understood.” (Mazzarella and Scafetta, 2018)”
by J. Van Vliet, Sep. 5, 2019 in ScienceClimatEnergie
Belgium and France were recently affected by an extreme heat wave that took place between 24 and 27 July 2019. This heat wave was in many aspects presented as unprecedented and it has therefore unlocked a large scale reaction by many media. After a few days to cool down, the time has come to express a non-emotional and non-political opinion about such a strong heat wave.
Emotional reactions were normal in such circumstances: the temperatures were extreme and even if France and Belgium were much better prepared that for the 2003 heat wave, the present heat wave has led to important suffering for many poor people or people in bad health and without access to air conditioning.
The heat wave unlocked also many political reactions: it was an opportunity to press once more the threatening mantra of United Nations and IPCC that mankind is responsible for this catastrophic warming and is destroying its own and only planet. A whole caste of politicians, countless academics and so-called “experts”, lobbyists, bureaucrats and NGOs claim that it is urgent to take “strong” measures going up to the replacement of democracy by climatist despotism: even children are enlisted in the political arena. These people number in hundreds of thousands and probably more and they communicate loudly and repeatedly at the UN, through IPCC reports and COP events, in the media and in the streets. Does this imply they are right ? Has mankind something to do with these high temperatures ?
by Cap Allon, November 19, 2018 in PrincipiaScientificInternational
Professor Valentina Zharkova explains and confirms why a “Super” Grand Solar Minimum is upon us: “If the world was looking for an Epiphany moment, this should be it.”
Professor Zharkova gave a presentation of her Climate and the Solar Magnetic Field hypothesis at the Global Warming Policy Foundation in October, 2018. Even if you believe the IPCC’s worst case scenario, Zharkova’s analysis blows any ‘warming’ out of the water.
Lee Wheelbarger sums it up: even if the IPCC’s worst case scenarios are seen, that’s only a 1.5 watts per square meter increase. Zharkova’s analysis shows a 8 watts per square meter decrease in TSI to the planet.
The information she unveiled should shake/wake you up. Zharkova was one of the few that correctly predicted solar cycle 24 would be weaker than cycle 23 – only 2 out of 150 models predicted this. Her models have run at a 93% accuracy and her findings suggest a SuperGrand Solar Minimum is on the cards beginning 2020 and running for 350-400 years.
by Passant Rabbie, July 31, 2019 in Space
A tsunami of plasma rushes through the sun before a new sunspot cycle begins.
Astronomers may have finally figured out what causes the sun’s 11-year cycle of activity, and it involves a “tsunami” of magnetic fields.
The sun, like other stars, goes through a cycle marked by a change in magnetic activity, levels of radiation, and the number and size of sunspots. While our sun’s 11-year cycle was discovered more than a century ago, predicting exactly when one cycle ends and a new one begins has been an ongoing challenge.
A pair of related studies have mapped out the sun’s activity over the course of 140 years, looking for clues about the solar cycle that are visible on the surface. By looking at the way bright flashes of ultraviolet light migrate across the sun’s surface, the researchers discovered that the sun’s mysterious 11-year cycle may be marked by a “terminator” event that ends one cycle and a “tsunami” of magnetic fields that initiates a new one. Those bright flickers of ultraviolet light and the sun’s magnetic fields appear to drive the cycle itself, and monitoring those flashes could help scientists predict when a new cycle will begin.
by G. Lloyd, July 15, 2010 in ClimateChangeDispatch
Sand deposits near the Gobi Desert in China may seem a strange place to look for evidence that cosmic rays can control how clouds are formed and the impact they have on Earth’s climate.
But Japanese scientists have measured the size of sand grains and the distance they traveled 780,000 years ago to add a new level of understanding to one of the questions that continue to baffle climate science: clouds.
The findings, published in Nature, point to big trends in natural variation of past and future climate that operate apart from greenhouse gas levels.
The study adds weight to a contentious theory by Danish researcher Henrik Svensmark, of the Danish National Space Institute in Copenhagen, which uses cosmic rays and clouds to question the sensitivity of climate to carbon dioxide in the atmosphere.
by F. Bosse & F. Vahrenbolt, June 22, 2019 in NoTricksZone
In May 2019 our sun was below-normal active again. The solar sunspot number (SSN) was 10.1, which is only 52% of the mean value in the evaluated cycle month no. 126 since the start of Cycle No. 24 began in December 2008.
It should be noted that the number of cycles that lasted this long is decreasing. In the previous month we reported on cycles 21, 18, 16, 15, 8 dropping out because they were shorter in total, and now SC 17 is getting added. Next month month SC 7 is will fall as well. The mean value thus becomes less meaningful as the end of the cycle approaches. But out of habit, we want to keep it nevertheless as comparison.
The activity in the past month was shifted very asymmetrically to the solar northern hemisphere, the southern hemisphere was spotless throughout the whole month. The solar north saw spots only on 15 days.
Fig. 2: Sunspot activity of the individual cycles since the beginning of cycle 1 in the year 1755. The numbers are computed by adding up the monthly differences of the observed cycles to the mean value, up to the current cycle month no. 126.
by A. Watts, June 21, 2019 in WUWT
Are we in a solar grand minimum? We’ve seen this before, but now predictions are for an extremely weak solar cycle ahead.
Today is the summer solstice in the northern hemisphere. The sun has been without a single observable sunspot now for over a month – 33 days according to NOAA and SIDC data.
Daily observations of the number of sunspots since 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 recent low sunspot activity is clearly reflected in the recent low values for the total solar irradiance. Compare also with the geomagnetic Ap-index. Data source: WDC-SILSO, Royal Observatory of Belgium, Brussels. Last day shown: 31 May 2019. Last diagram update: 1 June 2019 . [Courtesy climate4you.com]
by J. Goslin in P. Gosselin, June 1, 2019 in NoTricksZone
Another new paper, which of course will be ignored by the government-funded IPCC because it contradicts claims CO2 drives climate, shows that natural factors dominated the earth’s climate variability.
A team of scientists led by Jerome Goslin have published a paper titled Decadal variability of north-eastern Atlantic storminess at the mid-Holocene: New inferences from a record of wind-blown sand, western Denmark in the journal Global and Planetary Change, suggesting climate variability is driven naturally.
Image: NASA, public domain
Climate change driven by solar and oceanic cycles
Not surprisingly, as evidenced by hundreds of other publications (which are entirely ignored by the IPCC), climate variability is indeed tied to solar activity and “internal atmospheric and oceanic modes”.
by A. Jacobs & A. Préat, May 20, 2019 in SSRN.Elsevier
The focus of this study is based on a detailed analysis of the hyperthermal events of the
Paleocene / Eocene limit of 56 Ma and the lower Eocene (for the 54-52 Ma interval, Figure 1).
This example will show that the Earth has experienced many times much higher temperatures
than today, with warmer, sometimes more acidic oceans and an atmosphere much richer in CO2
(or CH4) than the current one. Are these past events precursors of the current situation?
Keywords: global warming, climate change, Paleocene, Eocene, hyperthermal events
by Joe Bastardi, May 17, 2019 inThePatriotPost
Apparently, the new strategy to fight climate change is shock therapy. It’s like today’s environmental crusaders are channeling the Ramones song “Gimme Gimme Shock Treatment.” Here are some illustrations.
Shock treatment is for extreme measures. But take, for example, this Dr. Willie Soon plot of solar irradiance (a measure of solar energy) vs. water vapor:
Water vapor is the number-one greenhouse gas. So it’s no secret what temperatures do when water vapor increases.
by Prof. F. Vahrenholt and F. Bosse, May 7, 2019 in NoTricksZone
If we speak of an average of the last 23 cycles in the months of the minimum, our only significant energy source at the center of the solar system was below average active last month as well.
The sunspot number (SSN) was 9.1, which was thus only 42% of the average of the cycles for month no. 125. Some cycles (No. 21, 18, 16, 15, 8 ) were already completed in month no. 125.
Fig. 1: The monthly sunspot activity of the current solar cycle (SC 24) since December 2008 (red) compared to the mean value of all previously systematically observed cycles since the beginning of SC 1 in March 1755 (blue) and the very similar SC 5 (black).
Figure 1 clearly shows that the latest cycle was quite below-normal, especially at the beginning and after the second peak which had an SSN of over 140 towards the end. Since February 2014 (the maximum of the entire cycle 24 with SSN = 146 in cycle month 63), it only reached 2/3 of the average activity.
What are the effects? The total radiation (TSI for total solar irradiance) is only moderately influenced:
par Jean N., 4 mai 2019 in Science-Climat-Energie
Dans une récente publication de 2019, l’équipe russe de G.A. Zherebtsov présente un mécanisme permettant d’expliquer le réchauffement global. Ce mécanisme, basé sur une série d’observations, ne fait pas intervenir le taux de CO2 atmosphérique mais les rayons cosmiques solaires ainsi que le champ électromagnétique terrestre. Les chercheurs qui ont pensé à ce mécanisme (inconnu du GIEC) font tous partie de l’institut de Physique Terrestre et Solaire de la Branche Sibérienne de l’Académie Russe des Sciences (Irkutsk, Russie). Si le mécanisme de l’équipe de Zherebtsov est correct, on pourrait alors se passer de l’hypothèse de l’effet de serre radiatif qui, comme vous le savez peut-être, pose certains problèmes (voir ici, ici et ici). Le but du présent article est simplement de présenter ce mécanisme et de montrer par la même occasion que la science du climat est loin d’être dite.
1. Observations réalisées le 7 novembre 2004
Les chercheurs russes ont d’abord constaté qu’à certaines latitudes il y a un lien assez fort entre le flux de rayons cosmiques solaires (RCS) et la température de la troposphère. Ceci est par exemple bien visible dans un évènement qui a débuté le 7 novembre 2004 au niveau des hautes latitudes de l’hémisphère nord (55°N-65°N). Ce jour-là, le flux de RCS était particulièrement fort d’environ 3 ordres de grandeur plus élevé par rapport à la normale (Figure 1a). Une tempête géomagnétique s’est ensuite déclarée le jour suivant et a duré au moins 5 jours (il s’agit de fluctuations brusques et intenses du magnétisme terrestre qui proviennent d’une perturbation de l’ionosphère par l’activité solaire). Ceci est bien visible sur le tracé des indices géomagnétiques AE (Figure 1b) et Dst (voir aussi ici), indices obtenus par certaines stations de mesure placées au sol et réparties en divers endroits de la planète (Figure 1c). Il existe de nombreux indices géomagnétiques et il n’est pas nécessaire d’être un spécialiste pour comprendre la suite du présent article. Il faut simplement retenir que le champ magnétique terrestre est perturbé les jours suivant l’arrivée des RCS. Voyons maintenant si tout ceci peut avoir un effet sur la température de la basse troposphère.
Figure 4. Diagramme présentant le mécanisme de Zherebtsov. Source : Zherebtsov et al. (2019) J Atm Solar Terrestrial Physics 182:217–222 (traduit de l’anglais).
by Zherebtsov G.A. et al., April 2019 in J.Atm&SolarTerrestrialPhysics
by F. Bosse and F. Vahrenholt, March 29, 2019 in NoTricksZone
The sun was also very sub-normally active in February. Although we are in the middle of the minimum, the sunspot number of 0.8 for the 123rd month into the cycle is very low. On 26 days of the month no spots were visible, only on 2 days was there a little, symmetrically distributed over both solar hemispheres.The only exciting question currently: When will the minimum be finished and will solar cycle 25 begin? Although 6 spots of the new cycle were already visible in February with a significantly higher resolution, estimates are difficult.March again was dominated by some spots of the “old” SC24. The rule: “weaker cycles often last longer than stronger cycles” could hold.
Figure 2: The strength of the sunspot activity of each cycle in comparison. The numbers in the diagram are obtained by adding up the monthly deviations between the observed values and the mean value (blue in Fig.1) up to the current 123rd cycle month.
Figure 2 shows that five cycles (No. 8, 15, 16, 18, 22) did not have a month 123 at all. Instead the following cycle started. In this respect, the picture is now somewhat distorted towards the end of the cycle.
See also here in GWPF
by Anthony Watts, March 12, 2019 in WUWT
Something this big today would surely fry electrical grids, GPS, and communications. It may be bigger than the Carrington Solar event of 1859.
Scientists have found evidence of a huge blast of radiation from the Sun that hit Earth more than 2,000 years ago. The result has important implications for the present, because solar storms can disrupt modern technology.
The team found evidence in Greenland ice cores that the Earth was bombarded with solar proton particles in 660BC. The event was about 10 times more powerful than any since modern instrumental records began.
The Sun periodically releases huge blasts of charged particles and other radiation that can travel towards Earth.
The particular kind of solar emission recorded in the Greenland ice is known as a solar proton event (SPE). In the modern era, when these high-energy particles collide with Earth, they can knock out electronics in satellites we rely on for communications and services such as GPS.
in GWPF, March 11, 2019
London, 11 March: A new report from the Global Warming Policy Foundation reveals that the solar influence on climate is is much larger than is generally recognised.
The report, by Professor Henrik Svensmark of the Danish National Space Institute, outlines some of the remarkable correlations between solar activity and past climate changes. It also shows that the output of the Sun alone – the so-called total solar irradiance – cannot explain them.
“Changes in total solar irradiance are actually quite small”, says Professor Svensmark. “They would have to be nearly 10 times larger to explain how the oceans warm and cool over the 11-year solar cycle.”
New research suggests that other mechanisms can amplify the effect of solar activity. The New report reviews the possible candidates, concluding that the most likely of these is the effects of galactic cosmic rays on cloud formation. This idea is plausible in theory and has received substantial empirical support in recent years.
However, Professor Svensmark says that insufficient attention is being paid to this research area:
“Galactic cosmic rays seem to be very important drivers of the Earth’s climate. But they are mostly being ignored at the moment because they are seen as distracting from conventional global warming research. Science needs to do better if we want to make progress in understanding the actual impact of natural factors of climate change.”
Henrik Svensmark: Force Majeure – The Sun’s Role In Climate Change (PDF)
About the author
Prof Henrik Svensmark is a physicist and a senior researcher in the Astrophysics and Atmospheric Physics Division of the National Space Institute (DTU Space) in Lyngby, Denmark. Svensmark presently leads the Sun–Climate Research group at DTU Space.
by Dr Tony Phillips, March 6, 2019 in SpaceWeatherArchive
March 1, 2019: There are 28 days in February. This year, all 28 of them were spotless. The sun had no sunspots for the entire month of Feb. 2019. This is how the solar disk looked every day:
How does this affect us on Earth? The biggest change may be cosmic rays. High energy particles from deep space penetrate the inner solar system with greater ease during periods of low solar activity. Indeed, NASA spacecraft and space weather balloons are detecting just such an increase in radiation. Cosmic rays can alter the flow of electricity through Earth’s atmosphere, trigger lightning, potentially alter cloud cover, and dose commercial air travelers with extra “rads on a plane.”
As February ended, March is beginning … with no sunspots. Welcome to Solar Minimum!
by P. Homewood, February 18, 2019 i
Here’s the text from the original page (my bolding).
The Sun is the primary forcing of Earth’s climate system. Sunlight warms our world. Sunlight drives atmospheric and oceanic circulation patterns. Sunlight powers the process of photosynthesis that plants need to grow. Sunlight causes convection which carries warmth and water vapor up into the sky where clouds form and bring rain. In short, the Sun drives almost every aspect of our world’s climate system and makes possible life as we know it.
Earth’s orbit around and orientation toward the Sun change over spans of many thousands of years. In turn, these changing “orbital mechanics” force climate to change because they change where and how much sunlight reaches Earth. (Please see for more details.) Thus, changing Earth’s exposure to sunlight forces climate to change. According to scientists’ models of Earth’s orbit and orientation toward the Sun indicate that our world should be just beginning to enter a new period of cooling — perhaps the next ice age.
Repost from JoNova
by P. Gosselin, February 17, 2019 in NoTricksZone
Today any warming found anywhere almost always gets blamed on heat supposedly getting trapped by rising atmospheric CO2 concentrations. Moreover, activist scientists insist we ignore all other powerful factors such as solar and oceanic cycles.
In fact these activists have become so extreme that they insist that record cold today is caused by warming.
But as people learned already in the first grade, the earth’s surface warms when the sun shines on it, and tends to cool when clouds obstruct the sun.
Solar radiation at the surface has risen over the past decades
In Japan, the Japanese Meteorology Agency (JMA) has 8 stations that measure solar radiation reaching the surface, and many other for recording temperature.
Data from the 8 stations recording solar radiation are plotted since 1999 (i.e. 20 years) as follows:
Data source: JMA