The human impact on the kelp forests occurs in two ways. One of these ways is that we basically killed the majority of the sea otters. This impact allowed sea urchin populations to go around almost unchecked and eat as much kelp as they can. Another way that we have impacted the environment is that we have caused global warming. This then leads to less available area for the kelp forest of alaska to grow. It can freely go grow up north during the summer but farther down along the pacific coast of the United States it is becoming progressively harder for kelp to grow as warmer waters are there.