Something real to worry about climate-wise

Our long term problem with climate is not warming but catastrophic cooling. The temperature record from the Vostok Ice cores demonstrates that climate conditions conducive to our civilization are vanishingly rare.  The little red box is the time in which our civilization has arisen.  John Holdren, the White House Science adviser has hypothesized that any global warming man creates might serve to moderate the cooling catastrophe that is already ever so slowly beginning. So yay CO2?