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by supercow12 2433 days ago
The IPCC report is massive with every single thing painstakenly cited, sourced and explained.

For example: https://www.ipcc.ch/site/assets/uploads/2018/02/WG1AR5_TS_FI...

>"Solar forcing is the only known natural forcing acting to warm the climate over the 1951–2010 period but it has increased much less than WMGHG forcing, and the observed pattern of long-term tropospheric warming and stratospheric cooling is not consistent with the expected response to solar irradiance variations. Considering this evidence together with the assessed contribution of natural forcings to observed trends over this period, it is assessed that the contribution from solar forcing to the observed global warming since 1951 is extremely unlikely to be larger than that from WMGHGs. Because solar forcing has very likely decreased over a period with direct satellite measurements of solar output from 1986 to 2008, there is high confidence that changes in total solar irradiance have not contributed to global warming during that period. However, there is medium confidence that the 11-year cycle of solar variability influences decadal climate fluctuations in some regions through amplifying mechanisms. {8.4, 10.3; Box 10.2} "

So there are multiple avenues of evidence that conclude that solar forcing isn't the cause of the temperature increase. This includes direct measurements of "total solar irradiance" (TSI).

And the numbers at the bottom in brackets? Those are sources for the claims made in that paragraph!

10.3 and "Box 10.2": https://www.ipcc.ch/site/assets/uploads/2018/02/WG1AR5_Chapt...

The above source even has an explanation for how the causes are determined: "FAQ 10.1 | Climate Is Always Changing. How Do We Determine the Causes of Observed Changes?"

Here is "8.4": https://www.ipcc.ch/site/assets/uploads/2018/02/WG1AR5_Chapt...

>"Total solar irradiance (TSI) measured by the Total Irradiance Monitor (TIM) on the spaceborne Solar Radiation and Climate Experiment (SORCE) is 1360.8 ± 0.5 W m–2 during 2008 (Kopp and Lean, 2011) which is ~4.5 W m–2 lower than the Physikalisch-Meteorologisches Observatorium Davos (PMOD) TSI composite during 2008 (Frohlich, 2009).The difference is probably due to instrumental biases in measurements prior to TIM."

The don't rely on single measurements of "total solar irradiance" either.

> "Since 1978, several independent space-based instruments have directly measured the TSI. Three main composite series were constructed, referred to as the Active Cavity Radiometer Irradiance Monitor (ACRIM) (Willson and Mordvinov, 2003), the Royal Meteorological Institute of Belgium (RMIB) (Dewitte et al., 2004) and the PMOD (Frohlich, 2006) series. "

The above claim that "all energy from the sun that is not a part of a specific EMR spectrum" is missing when the conclusions were drawn is just plain wrong.

from 8.4:

>"Solar spectral irradiance (SSI) variations in the far (120 to 200 nm) and middle (200 to 300 nm) ultraviolet (UV) are the primary driver for heating, composition, and dynamic changes of the stratosphere, and although these wavelengths compose a small portion of the incoming radiation they show large relative variations between the maximum and minimum of the SC compared to the corresponding TSI changes. As UV heating of the stratosphere over a SC has the potential to influence the troposphere indirectly, through dynamic coupling, and therefore climate (Haigh, 1996; Gray et al., 2010), the UV may have a more significant impact on climate than changes in TSI alone would suggest. Although this indicates that metrics based only on TSI are not appropriate, UV measurements present several controversial issues and modelling is not yet robust.

Multiple space-based measurements made in the past 30 years indicated that UV variations account for about 30% of the SC TSI variations, while about 70% were produced within the visible and infrared (Rottman, 2006). "

It is correct that UV is only 30% of TSI. Hence why TSI was used to make conclusions about the impact of "solar forcing" on the climate instead of just UV.

The links I give are to just a couple sections of just one of the reports (the "physical science basis" one).

Here is the full "physical science basis" report: https://www.ipcc.ch/report/ar5/wg1/

1 comments

I’m afraid your comment completely ignores the only point I made in my comment...

TSI stands for total solar irradiance. This is the EMR spectrum I’m referring to. If you continue to read the report from the IPCC, you will notice there is no mention of energetic particle precipitation (EPP), or any particle forcing of any kind.

So yes, the IPCC report is extraordinarily thorough and exactly perfect in everything that it purports to be; unfortunately it completely leaves out the largest part of the equation. Please see my analogy above.

It indeed doesn't mention EPP.

Is there any proof that EPP is significant?

What about the other parts of the report?

For example:

>"It is extremely likely that human activities caused more than half of the observed increase in global average surface temperature from 1951 to 2010. This assessment is supported by robust evidence from multiple studies using different methods. In particular, the temperature trend attributable to all anthropogenic forcings combined can be more closely constrained in multi-signal detection and attribution analyses. "

In order for climate change to be primarily driven by EPP or particle forcing instead of anthroprogenic forcing, it would have to be the case that either:

A. Somehow, anthroprogenic forcing is much less than the multiple avenues of evidence show. Here:

https://www.ipcc.ch/site/assets/uploads/2018/02/WG1AR5_Chapt...

https://www.ipcc.ch/site/assets/uploads/2018/07/WGI_AR5.Chap...

https://www.ipcc.ch/site/assets/uploads/2018/02/WG1AR5_TS_FI...

https://www.ipcc.ch/site/assets/uploads/2018/02/WG1AR5_Chapt...

or

B. There is something unknown that offsets the impact of anthroprogenic forcing, but would not have offset the impact of particle forcing in the absence of anthroprogenic forcing.

In the absence of evidence, it is a big claim to make that either of these things are the case.

There is no direct evidence of specific amounts of temperature rise that can somehow magically be attributed to human activities (e.g., we are able to measure all energy values of every single thing on earth and then determine what causes what exactly, etc.). Nobody even claims that this is the case; certainly not the IPCC.

The conclusion (temperature-changing effects of human activities) is derived specifically from taking the local maxima of warming we’ve seen in this very short window, subtracting the known non-human factors (of which the sun is one... hence the importance of the missing data), and then attributing the rest to human activities.

In other words, your statements, pertaining how we can deduce that their conclusions are correct, save for A or B (above), are the most quintessential example of “begging the question”.

Another important bit that I didn’t even mention in my original comment is that, not only does looking at TSI ignore other particle forcing qualities of solar phenomenon, such as flares and sunspots, But it also ignores the fact that, during such events, solar irradiance is measurably decreased. This means that the assumed human factor needed to justify the perceived temperature increase in the models is actually raised in such cases. This means that when using the models to predict the temperature on the earth, the models will actually predict that human activities that cause warming increase during solar events.