Archives par mot-clé : Sun

Israeli Astrophysicist rejects UN IPCC – Finds ‘the sun completely overturns the way we should see global warming’

by Dr. Shaviv, November 9, 2017 in ClimateDepot


(…)The body of evidence however clearly shows that the climate sensitivity is on the low side, about 1 to 1.5 degree increase per CO2 doubling. People in the climate community are scratching their heads trying to understand the so called hiatus in the warming. Where is the heat hiding? While in reality it simply points to a low sensitivity.

Most Modern Warming, Including For Recent Decades, Is Due To Solar Forcing, Not CO2

by Kenneth Richard, November 9, 2017 in NoTricksZone


Though advocates of the dangerous anthropogenic global warming (AGW) narrative may not welcome the news, evidence that modern day global warming has largely been driven by natural factors – especially solar activity – continues to pile up.

Much of the debate about the Sun’s role in climate change is centered around reconstructions of solar activity that span the last 400 years, which now include satellite data from the late 1970s to present.

Radiation Transfer Calculations and Assessment of Global Warming by CO2

by Hermann Harde, March 30, 2017 in Inter.J.Atm.Sciences


Including solar and cloud effects as well as all relevant feedback processes our simulations give an equilibrium climate sensitivity of = 0.7°C (temperature increase at doubled CO2) and a solar sensitivity of = 0.17°C (at 0.1% increase of the total solar irradiance). Then CO2 contributes 40% and the Sun 60% to global warming over the last century.

Are cold winters in Europe associated with low solar activity?

by M. Lockwood et al., April 2010, in EnvironmResLetters


Solar activity during the current sunspot minimum has fallen to levels unknown since the start of the 20th century. The Maunder minimum (about 1650–1700) was a prolonged episode of low solar activity which coincided with more severe winters in the United Kingdom and continental Europe. Motivated by recent relatively cold winters in the UK, we investigate the possible connection with solar activity. We identify regionally anomalous cold winters by detrending the Central England temperature (CET) record using reconstructions of the northern hemisphere mean temperature.

Solar Cycle Continues To Be The Weakest In 2 Centuries

by  F.  Bosse and  F. Vahrenholt, August 23, in NoTricksZone


The sun was completely free of spots on 11 days in July. Notable: while during last month the sun’s northern hemisphere was more active (in June all sunspots were in the northern hemisphere), last month the southern hemisphere was the most active part with 60% of the sunspots appearing there. The following diagram shows the course of solar cycle 24 thus far (…)

The Effects of the Bray Climate and Solar Cycle

by Andy May, August 8, 2017 in WUWT


The Bray cycle is about 2450 years from beginning to end and the Bray Lows, which are the coldest portion of the cycle, are the most important events.

The world is currently within the Quaternary Ice Age and nearly as cold as it has ever been. The normal average temperature of the world is around 20°C, some 5°C warmer than today. To keep recent warming in perspective, it is important to understand that even if the worse predictions of the IPCC were to occur, we would only be returning to the average temperature of the last 560 million years

Phanerozoic Global Temperature from Scotese 2015,

link in the post (.pdf)

Does Belgian Holocene speleothem records solar forcing and cold events?

by M. Allan et al., July 11,  2017, in Climate of the Past


We present a decadal-centennial scale Holocene climate record based on trace elements contents from a 65 cm stalagmite (“Père Noël”) from Belgian Père Noël cave. Père Noël (PN) stalagmite covers the last 12.7 ka according to U/Th dating. High spatial resolution measurements of trace elements (Sr, Ba, Mg and Al) were done by Laser- Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). Trace elements profiles were interpreted as environmental and climate changes in the Han-sur-Lesse region.

See also here

Closely Coupled: Solar Activity and Sea Level

by David Archibald, July 3, 2017


From a post a couple of days ago: “an F10.7 flux above 100 causes warming and below that level causes cooling.” Greg asked “Can you prove that?” I already had in this WUWT post from 2012. But it is worth revisiting the subject because it answers the big question – If all the energy that stops the Earth from looking like Pluto comes from the Sun, what is the solar activity level that corresponds to our average climate? Because solar activity is falling and climate will follow.

Lowest Solar Activity In 200 Years Accompanied By High Northern Hemispheric Snow And Ice

by P. Gosselin from F. Bosse and F. Vahrenholt, June 18, 2017


In May the sun was very quiet as sunspot number was a mere 18.8, which is only 36% of what is typical for the month this far into the cycle. Seven days saw no sunspot activity at all.

The following chart shows the current cycle, Solar Cycle 24 (red), compared to the mean of the previous cycles (blue) and the similarly behaving SC 5 (black).

It’s clear that the current cycle is significantly weaker than the mean and far weaker than the cycles we saw throughout most of the warming 20th century.