See this article reporting research from Sweden regarding climate change in the North and South Atlantic basin. Using data from the last 10,000 years, they find that when the north is warm, the south is cold and vice versa.
Be clear, they aren't talking about the annual switch from summer in the north to summer in the south. Instead, for prolonged periods the North Atlantic area will be warm while the South Atlantic area will be cold, then north and south trade climates.
The Swedish researchers believe this variation is driven by changing ocean currents. These same currents influence the frequency and intensity of hurricanes.
