The pattern of recent surface warming observed in the Arctic exhibits both polar amplification and a strong relation with trends in the Arctic Oscillation mode of atmospheric circulation. Paleoclimate analyses indicate that Arctic surface temperatures were higher during the 20th century than during the preceding few centuries and that polar amplification is a common feature of the past. Paleocl...

The effect of rapid phase change on chirped continuum pulses is studied with a frequency-domain interferometer. Because of the chirp, temporal evolution of the optical Kerr response in CS(2) is projected into difference phase spectra. The chirped continuum shows spectral shifts that are due to induced phase modulation even when the continuum has a flat spectrum.