This is exactly true. And one point I want to make is that we haven't studied for long enough to have determined whether or not we are in a trough as far as temperatures are concerned.
The other thing is, Solar activity plays a huge role in atmosphere. In fact, it is the #1 driver of our climate. There are a number of scientists declaring that the sun appears to be going into a period of hibernation, which would cause the atmosphere of earth to cool to a large degree. There was a period in fairly recent history when the River Thames was frozen. And there are a number of people who are of the opinion that the Delaware River was frozen over as depicted in the famous painting by Emanuel Gottlieb Leutze called "Washington Crossing the Delaware".
I've heard one solar scientist stating that as the sun gets more quiet, the earth will experience more volcanoes and earthquakes. As the planet begins to cool it's going to contract, putting pressure on everything under the crust resulting in: earthquakes and lava flows like popped pimples.