摘要：During the descent into the recent 'exceptionally' low solar minimum, observations have
revealed a larger change in solar UV emissions than seen at the same phase of previous
solar cycles. This is particularly true at wavelengths responsible for stratospheric ozone
production and heating. This implies that 'top-down' solar modulation could be a larger
factor in long-term tropospheric change than previously believed, many climate models
allowing only for the 'bottom-up' effect of the less-variable visible and infrared
solar emissions. We present evidence for long-term drift in solar UV irradiance,
which is not found in its commonly used proxies. In addition, we find that both
stratospheric and tropospheric winds and temperatures show stronger regional
variations with those solar indices that do show long-term trends. A top-down
climate effect that shows long-term drift (and may also be out of phase with
the bottom-up solar forcing) would change the spatial response patterns and
would mean that climate-chemistry models that have sufficient resolution in the
stratosphere would become very important for making accurate regional/seasonal
climate predictions. Our results also provide a potential explanation of persistent
palaeoclimate results showing solar influence on regional or local climate indicators.
