Unfortunately the paper is in German

http://www.eike-klima-energie.eu/news-cache/abschaetzung-der-globalen-erwaermung-durch-co2-und-solaren-einfluss/

That sounds about right to me. I know that most of the dire effects you hear all the time are caused by secondary effects because the CO2 alone is a pretty small effect. And those feedbacks are REALLY hard to predict, which is why the forecasts are all over the place.

If it is true why hasn't Harde submitted his paper to one of the many pre-eminent scientific journals available?

Why does this laser spectroscopist specialized in electrical engineering always submit his papers to the most obscure 'open journals' available? There's lots of these popping up all the time and most if not all are used to artificially inflate mediocre scientists' CV's, not for the advancement of Science.

Not surprisingly, the 'Open Journal of Atmospheric and Climate Change' is on Beall's List of Predatory Open Access Publishers.

Sure it's true, but the science doesn't fit the political narrative of so-called "global warming". Co2 levels have increased a scant 0.012% since the 1900's and adding another 0.01% of a trace gas will have no effect on the climate at all.

So suddenly Watts is a fan of models but unknown people who are not who they claim to be and don't publish in a real journal. (Meaningful work is published in real journals to share with other researchers). His claim that Harde's estimate is 7 times less is a flat out lie design to fool stupid people (and that seems to work for him). Watts his comparing Harde's no-feedback calculations to the IPCCs total ECS; these are not comparable. This is a perfect example of why educated people do not consider Watts a good source for anything. (And a good example of why his neighbors fired him from the Chico CA school board. People who know him don't trust him.)

http://blog.hotwhopper.com/2014/10/antho...

The IPCC estimate range of climate sensitivity comes from a wide net of research using various methods by real people publishing in real journals.