Humans DID it!!!
green house gases!!!!
When green house gases go into the atmosphere they trap energy, which makes it hotter, and makes ice and arctic lakes melt.
Transportation, electricity, and industries cause pollution and ice to melt its get hotter from carbon dioxide which makes green house gases which causes it to get hotter. By CO2 turning in to green house gasses, and going into the atmosphere.
Carbon dioxide levels are rising
People create fossil fuels by cranking there cars and other activities they also create green house gases.Which gases into into the atmosphere and when there is to much it causes it too get hotter.Heat travels the atmosphere and oceans.This makes the ice caps melt and the lakes drain out into the ocean. Also 40% of ice cover has melted in a few years.Green house gases trap heat and makes it hotter if this continues the temp. will rise it gets hotter the ice melts the ocean will rise and the ice level will decrease.