Lake Baikal and the weather

At www.sciencedaily.com/releases/2011/02/110217091132.htm Lake Baikal, the worlds biggest lake, we learn is cold and deep and is giving up some of its secrets. A study in PLoS One (February 2011) by Russian scientists has found that water temperatures in the past correlate with El Nino indices and actually reflect sea surface temperatures in the Pacific – yet Lake Baikal is in Siberia. Basically, the lake appears to be responding to the position of the Jet Stream and although, in recent years, there has been evidence of warming the longer trend is not in a single direction. In other words the temperature of the lake is dependent on the 60 year Sun cycle and it is this which influences the El Nino dominance (or conversely the La Nina prevalence) as well as ocean surface temperatures – but the paper fails to actually say that. Why?