One of the biggest criticisms levied against Svensmark was that he had used data from a satellite that did not measure
total global cloud cover.
Not exact matches
«
Global mean time series of surface - and satellite - observed low - level and total cloud cover exhibit very large discrepancies, however, implying that artifacts exist in one or both data sets... The surface - observed low - level cloud cover time series averaged over the global ocean appears suspicious because it reports a very large 5 % - sky - cover increase between 1952 and
Global mean time series of surface - and satellite - observed low - level and
total cloud cover exhibit very large discrepancies, however, implying that artifacts exist in one or both data sets... The surface - observed low - level
cloud cover time series averaged over the
global ocean appears suspicious because it reports a very large 5 % - sky - cover increase between 1952 and
global ocean appears suspicious because it reports a very large 5 % - sky - cover increase between 1952 and 1997.
«Moreover, changes in the heliospheric magnetic field have been linked with changes in
total cloud cover over the Earth, which may influence
global climate.
... Conclusions Since 1950,
global average temperature anomalies have been driven firstly, from 1950 to 1987, by a sustained shift in ENSO conditions, by reductions in
total cloud cover (1987 to late 1990s) and then a shift from low
cloud to mid and high - level
cloud, with both changes in
cloud cover being very widespread.
Cloud variations are obviously an important element on a global scale, but the effects of Arctic ice melting are important locally and also a non-trivial fraction of global albedo feedbacks, which are a contributor to total feedback that is smaller than those from water vapor and probably from cloud feedbacks, but not insignifi
Cloud variations are obviously an important element on a
global scale, but the effects of Arctic ice melting are important locally and also a non-trivial fraction of
global albedo feedbacks, which are a contributor to
total feedback that is smaller than those from water vapor and probably from
cloud feedbacks, but not insignifi
cloud feedbacks, but not insignificant.
6) The main
cloud bands move more poleward to regions where solar insolation is less intense and
total global albedo declines via a reduction in
global cloud cover due to shorter lines of air mass mixing.
16) The main
cloud bands move more equatorward to regions where insolation is more intense and
total global albedo increases once more due to longer lines of air mass mixing.
The size and intensity of the polar vortexes then has an effect on the latitudinal position of the jetstreams which then alters
total cloud quantities (and reflectance) so as to alter
global albedo and thereby alter solar energy input to the oceans.
Although we focus on a hypothesized CR -
cloud connection, we note that it is difficult to separate changes in the CR flux from accompanying variations in solar irradiance and the solar wind, for which numerous causal links to climate have also been proposed, including: the influence of UV spectral irradiance on stratospheric heating and dynamic stratosphere - troposphere links (Haigh 1996); UV irradiance and radiative damage to phytoplankton influencing the release of volatile precursor compounds which form sulphate aerosols over ocean environments (Kniveton et al. 2003); an amplification of
total solar irradiance (TSI) variations by the addition of energy in
cloud - free regions enhancing tropospheric circulation features (Meehl et al. 2008; Roy & Haigh 2010); numerous solar - related influences (including solar wind inputs) to the properties of the
global electric circuit (GEC) and associated microphysical
cloud changes (Tinsley 2008).
«The overall slow decrease of upwelling SW flux from the mid-1980's until the end of the 1990's and subsequent increase from 2000 onwards appear to caused, primarily, by changes in
global cloud cover (although there is a small increase of
cloud optical thickness after 2000) and is confirmed by the ERBS measurements... The overall slight rise (relative heating) of
global total net flux at TOA between the 1980's and 1990's is confirmed in the tropics by the ERBS measurements and exceeds the estimated climate forcing changes (greenhouse gases and aerosols) for this period.
Palle et al (cited elsewhere here) have shown that the
total albedo has decreased over the period 1985 - 2000, while
cloud cover also decreased (resulting in
global warming), and has reversed itself since then, with increased
cloud cover.
Thus if the two mid latitude jets move equatorward at the same time as the ITCZ moves closer to the equator the combined effect on
global albedo and the amount of solar energy able to penetrate the oceans will be substantial and would dwarf the other proposed effects on albedo from changes in cosmic ray intensity generating changes in
cloud totals as per Svensmark and from suggested changes caused in upper
cloud quantities by changes in atmospheric chemistry involving ozone which various other climate sceptics propose.
The main
cloud bands move more poleward to regions where solar insolation is less intense so
total global albedo decreases.
«
Global mean time series of surface - and satellite - observed low - level and total cloud cover exhibit very large discrepancies, however, implying that artifacts exist in one or both data sets... The surface - observed low - level cloud cover time series averaged over the global ocean appears suspicious because it reports a very large 5 % - sky - cover increase between 1952 and
Global mean time series of surface - and satellite - observed low - level and
total cloud cover exhibit very large discrepancies, however, implying that artifacts exist in one or both data sets... The surface - observed low - level
cloud cover time series averaged over the
global ocean appears suspicious because it reports a very large 5 % - sky - cover increase between 1952 and
global ocean appears suspicious because it reports a very large 5 % - sky - cover increase between 1952 and 1997.