This was followed by the very cold period of the 1800s, and then by rapid warming that started in about 1900. (sciencenordic.com)
There have been many warm periods, such as when the dinosaurs lived and many cold periods, such as the last ice age of about 20,000 years ago. (illconsidered.blogspot.ru)
Their study shows no acceleration and no changes in rate during warm or cold periods of the last 110 years. (climatechangefacts.info)