Environment Counts | Undersampling of the Arctic biases recent global average temperature trends :
Comparing the hybrid global temperature reconstruction and the raw HadCRUT4 data reveals that the warming trend since 1997 in the hybrid global reconstruction is two and a half times greater than that estimated from the coverage-biased HadCRUT4 data. Trends starting in 1997 or 1998 are particularly biased with respect to the global trend.
Temperature trend (Â°C per decade) for January 1997â€“December 2012
|Reconstruction||Trend (Â°C per decade)|
|HadCRUT4||0.046 Â± 0.063|
|Hybrid||0.119 Â± 0.076|