Just not recently. A new temperature reconstruction indicates that Southern Spain cooled steadily from 1350 to the late 1700s then warmed rapidly until early 1800s, after which temperatures have been variable but flat through to the present (h/t Kenneth Richards). The authors examined trees growing in the Cazorla National Park in Southeast Spain, some of which are now over 800 years old, and used their tree rings to find indications about climate conditions of the past. The authors of this paper (unlike, say, the authors of the hockey stick study) caution their readers that all such studies are very uncertain and tree rings may miss a lot of details about the local climate. But the temperature history they tentatively reconstruct looks nothing like the usual alarmist hockey stick. Aside from a warming spurt around 1800 there is no trend to be found. Moreover seven of the 10 warmest years occurred not after 2010 but before 1610, and the only one in the 20th century was back in 1961. After which two of the 10 coldest years occurred, in 1999 and 2005.
The lack of warming after the early 1800s in this particular proxy temperature record is remarkable since the concentration of CO2 has gone up by about 135 ppm over that interval. Unless CO2 isn’t the climate control knob the alarmists keep saying it is, in which case it’s not remarkable at all.
For that matter the sudden warming in the interval from 1780 to 1820 is also remarkable if CO2 is the control knob because CO2 didn’t change back then. Obviously something else caused any such warming and it had to have been natural in origin. So we can conclude that nature is capable of causing major warming trends in some geographic regions, and is also capable of ignoring the rise of CO2 in the atmosphere.
You heard it here first.