since 19th century, societies have grown based on the use of fuels, resources and land to meet their NECESSITIES. this has created an impact to the ENVIRONMENT, either by the pollution of the air or the destruction of nature. but people never see the damage they were doing until now, that we experience the impact. hotter temperatures, melting glaciers, animal EXTINCTION, DESERTIFICATION and destroyed habitats. those are the results of human impact on earth. if this keeps going at that RHYTHM, many flora and fauna could be gone by the next century. it may sound like a lot of time and perhaps we DON'T need to be worried because we ain´t going to BE alive by that time. but our kids, GRANDSONS will be and they are going to be carrying our fault . we need to act as soon as possible to change our ways to get energy and stop DESTROYING ECOSYSTEMS! this last decade the impacts have been more and stronger than ever.