Presently, our solar system is passing through the (Milky Way) Galactic Plain. Inevitably, this will lead to cosmic disruptions, increased volcanic activity, and possibly the current geomagnetic pole shift. It is not bizarre to think that if our solar system passes through an area of DARK MATTER, similar or worse disruptions could occur here on Earth.
Such pass-throughs could explain more about global warming than mere human carbon dioxide emissions. Solar reactivity would also increase, affecting Earth, and other planets, such as by exciting and heating the planetary cores, and so, atmospheres. Electrical dynamics would also become unstable and reactive.
These could also be accompanied by an increase of comets and meteors. (Perhaps, a swing of an external planet into the inner solar system could also be synchronised with a rhythm, of in-and-out of such fields.
Before the dinosaurs theoretically became extinguished by the impact of a large meteor or comet, the dinosaurs were already in decline. Why? (This same pattern occurred prior to the mass-extinctions of the Cambrian period - both beginning in the oceans, with greenhouse acidification and/or anoxia). It is because of MULTIFACTORAL! - There are reasons behind why comets hit, why planets warm, and so forth. These are all interrelated - and they may all tie into the passage of the solar system through certain plains or fields in the galaxy - or even in the universe.
With that said, here is a hypothesis from a scientist that the Dinosaurs were extinguished, (in synchrony with a meteor or comet impact), due to the passage of our solar system through a field of dark mass in the galaxy -
Did dark matter kill the dinosaurs? - http://www.redorbit.com/news/space/1113338066/did-dark-matter-cause-dinosaur-extinction-022015/