from Labrador, Newfoundland, and Nova Scotia very clearly reflect cooling at the time of the GSA.

DESER: And I'd like to emphasize that the decadal SST variability is clearly reflected in the atmosphere as high as the 50-mb level. It's influencing storm tracks, and in fact you can see it in rainfall over western Ireland.

BRYAN: This question of why we should measure deep-ocean temperature when the atmosphere can respond only to SST is a long-standing one. I think there are two reasons. The first is that the deep-sea signals are signatures of past events that may be important for unraveling both the mechanism and the magnitude of the exchanges of heat between the ocean and atmosphere. The second is that unless the temperature changes we see are perfectly compensated for by salinity, the thermohaline circulation is responding to the pressure fields within the ocean itself, and those circulation changes do have a large effect on SST in areas of strong currents.

GHIL: Pierre, I really think we can safely assume that the ocean is part of the climate system. Also, it seems to me that suggesting that all the ocean is good for is giving you SSTs is like saying that all the atmosphere is useful for is heat fluxes.

MOREL: Many phenomena in the ocean, like the tides, are not part of climate, any more than rainbows in the atmosphere are.

GOOS, as currently defined, covers everything that can be measured in the ocean, which is why I was asking about a sampling strategy. I feel that a cause-and-effect relationship between decadal variability in the ocean and decadal variability in the atmosphere needs to be shown before we can consider the former a climate phenomenon.

MARTINSON: That's odd; I would have said that the atmospheric moisture reflected in rainbows was part of climate.

ROOTH: Getting serious, now, the temperature anomalies on a 10-year time scale at OWS "C" mean that you can have fairly substantial changes in moist static energy at the surface. Being an old cloud-physics man, I think that we need to look at that, not just dry energy, as we try to feed ocean temperature back into climate. As for location of observation stations, we do need to understand the processes in the deep in the Atlantic, because of the deep-water formation and the convective effects, which involve large temperature differences. The deep circulation in the Pacific appears to be much less important to understanding what goes on at the surface on decadal time scales.

LEHMAN: It seems to me that I've been hearing some of the first evidence connecting ocean surface variability with real changes in the interior. I think modelers should really be homing in on this evidence of surface-to-deep-ocean coupling that directly implicates thermohaline circulation in the variability of the surface.



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