In fact, if i do a quick search on the list on the word "klima", only one name can be found, being Prof. Dr. Horst Malberg Universitätsprofessor (A.D.) für Meteorologie und Klimatologie. One. That's all.
And of course another name on the list is the infamous Ernst Beck (a high-school teacher),
whose methodology can be used to demonstrate both that C02 levels have fluctuated wildly over the course of the last century and a half, and that the value of π (Pi) has fluctuated wildly over the course of the last two millennium.
Jules Jules' klimaatblog further notes that the outfit behind this open letter, EIKE (Europäisches Institut für Klima und Energie) appears to be the German franchise of the International Climate Science Coalition, a denialist group headed up by Canada's own Tom Harris. If you look at their (EIKE's) "scientific council", you see all the usual suspects: Carter, Courtney, and rounded out with one dead guy--Marcel Leroux.