Is the recently reported 65-and 70-year surface-temperature oscillation the result of climatic noise?

In a recent paper, the authors reported finding a 65-to 70-year oscillation in each of the four records of observed global-mean surface temperature. It was also found that the oscillation does not exist everywhere over the earth, but rather only over the North Atlantic Ocean and its bordering continental regions of North America, Europe, and northern Africa. Three possible causes for this finding are proposed: (1) random radiative forcing of the climate system, that is, climatic noise, (2) oscillatory forcing external to the climate system, such as by a variation in solar irradiance, and (3) an oscillation internal to the climate system, perhaps not unlike that of the El Nino-Southern Oscillation, but with a longer timescale. This paper critically examines the first hypothesis. The analysis shows that this hypothesis can be rejected at a very high level of statistical confidence. (Authors)