UK Met Office: CO2 causes warming; other factors cause cooling — ‘We have known for some time that [multi-decadal oceanic cycles] may act to slow down or accelerate observed warming trend’
'We also know that changes in the surface temperature occur not just due to internal variability, but are also influenced by 'external forcings', such as changes in solar activity, volcanic eruptions or aerosol emissions. Combined, several of these factors could account for some or all of the reduced warming trend seen over the last decade – but this is an area of ongoing research'
