Click the tree logo at the very top to get to the Apple home page of the app or remember the ourclimate.info URL (old). AppShopper has a page, too. To actually buy the app, you need an Apple ID. When you have it, run your iTunes, search for Our Climate in the right upper corner, filter by apps, and you will see the tree logo once again.
itunes.com/apps/ourclimateThe result is a fantastic application sold for USD 0.99 (or EUR 0.79) whose real value is hundreds of dollars.
... (click to open app page directly in iTunes)
It offers you dozens of excellent articles of the right size, lots of pictures, graphs, quizes, world-wide polls, and more.