Recent news reports about a predicted decline in the sun's magnetic activity pose the question, asking if the earth will be cooling off because of it. Let's ask the Bad Astronomer, Dr. Phil Plait.
What follows is a pretty comprehensive but simply written explanation of the sun's magnetic cyle and its effect on Earth's temperature. Link
The answer — spoiler alert! — is almost certainly "no". I want to make sure that’s clear, because I will bet essentially any amount of money that some climate change denial sites will run with this story and claim that we don’t need to worry about global warming. That’s baloney, and what follows is why. The reasons take a minute to explain, but of course that’s where the cool stuff (haha!) is. So let’s take this one step at a time. And if you have the attention span of an E. coli bacterium, you can skip down to the conclusion section.
What follows is a pretty comprehensive but simply written explanation of the sun's magnetic cyle and its effect on Earth's temperature. Link
It takes balls to say something is badly written simply because it is too difficult (or "boring") for yourself to understand it.
If that explanation was too hard or too boring, try reading an official scientific paper, you know, like the ones articles like this one are based on.
We are in what is called an Interglacial. Heard of it? 12000 years ago, there was winter sea-ice in San Diego. Do you know where that is? Sea levels were 300 ft lower than they are today.
In the past million years there is an Interglacial every 100-40 thousand years, and they last about 20-40 thousand years.
At any rate, our Interglacial seems to have peaked around 3-4000 BC when sea levels were 10 ft higher than they are today. This puts about 8000 years before we enter the next Ice Age.
See http://image.absoluteastronomy.com/images/encyclopediaimages/a/at/atmospheric_co2_with_glaciers_cycles.gif