Motivation Letter (college) review, please?

Hi guys, I had all of a sudden known of the opportunity for me to apply the international college of my university, so I had to write this motivation letter but I fear it is not that good, because english is not my mother language...
Could you please review it? I just need to know if there are big mistakes or something like that, cause I don't have time to lengthen and improve it significantly. Really really thanks!!

Dear Madame/Sir
I am writing to apply for admission to the XXXX University International College. I am enrolled in the second year of the undergraduate program of Environmental Sciences. I grew a passion for this field of study as I realized how beautiful, yet fragile, Nature is.
In particular, I am interested in the issues of biodiversity conservation and sustainable development. I learned that humanity is facing a major challenge in this century: we must learn how to live within our ecological limits. I understand that my generation will have a key role in this direction. And how could we tackle global issues if not cooperating globally? Now more than ever, I feel that we should abandon our divergences and work together, internationally.
It is in this spirit that I would like to join the XXX University College: to meet students from around the world, to have a broader view, to breathe an international air. I think it would be an excellent way to prepare myself for the future.

Sincerely
Me