It’s time for a reality check: the world is changing as we speak! The latest report on global warming, published in Wednesday’s edition of the journal Nature, concluded that, on a global scale, physical and biological systems are changing at a rapid pace, mostly due to higher temperatures for which humans are responsible.

The increase in greenhouse emissions, which led to a striking climate change over the past decades, and was induced by human-related activities, is responsible for a series of changes that take place at global scale, and spread throughout all continents, from the early arrival of migratory birds in Australia, Europe and North America, to the shrinkage of glaciers and melting of permafrost.

Lead-author of the study Cynthia Rosenzweig of the NASA Goddard Institute for Space Studies and the Columbia Center for Climate Systems Research based her analysis on studies that have been tracking climate change related issues for the past four decades.

The paper comes to disagree with theories that refuse to put human activities at the core of climate changes. Several reports released over the years, including this March, support the idea that we are still far from being able to sustain theories according to which at the cause of global warming lie anthropogenic causes, rather than natural ones.

The team of scientists led by Cynthia Rosenzweig tried to take an impartial approach on the subject and draw a line between nature-related changes and anthropogenic-relates ones. The conclusion was that natural climate variations alone cannot be held responsible for all the changes that have been observed.

According to the study, over 90 percent of the changes (physical and biological) are related to warmer temperatures. Among them, the study includes the shrinking of glaciers and melting of permafrost on several continents, the earlier breakup of river and lake ice in Mongolia, the dramatically decreasing number of emperor penguins in the Antarctic Peninsula, the earlier arrival of migratory birds in Europe, North America and Australia, and many other.

There is absolutely no doubt that we are witnessing a climate change on a global scale. What we need to do now, Dr. Rosenzweig warned, is to learn to adapt to these changes, and most importantly, to act together in order to reduce the long-term risks.