It’s been a hot week for global warming.

NASA released global temperature data showing that this September tied with 2005 for the warmest September on record. That’s doubly impressive since 2005 was warmed by an El Niño and accompanying warm Pacific ocean temperatures, whereas 2013 has had cooler Pacific temperatures all year.

Greenhouse gases keep warming the planet to unprecedented levels with unprecedented speed. That’s the conclusion of two new studies out this week.

The first, ‘Unprecedented recent summer warmth in Arctic Canada,