What is Climate Change?

We hear the term all the time these days. But what does ‘Climate Change’ actually mean? Climate change means significant and lasting changes in weather patterns and other measures of the Earth’s climate. These changes can include rising or falling temperatures, increases and decreases of rainfall or snow, shifting water levels, as well as the frequency and intensity of storms, hurricanes and typhoons.

The Earth’s climate has been changing for many millions of years. The difference now is that scientists can see that humans have significantly affected climate change over the last 150 years. In a very short time, humans have made significant impacts on many different aspects of the Earth’s systems, including the atmosphere (the Earth’s air and climate), biosphere (life on the Earth), and pedosphere (the Earth’s soil). Many scientists now think that we have entered a new geologic era in which humans are fundamentally reshaping the Earth and its systems: they call it the Anthropocene Era because ‘anthropo’ means ‘human’ in Greek! Watch the video below to learn about the Anthropocene era, and how humans are rapidly changing the way the Earth operates:

To get a better picture of the Anthropocene,  let’s look at the geologic time scale. The Quaternary is the current period of the Earth’s history, which started around 2.5 million years ago with the Ice Ages. The Quaternary is divided into three epochs, or periods: the Pleistocene, the Holocene, and now the Anthropocene. Click on the time scale below for a closer look:


The Pleistocene (2.5 million years ago to 11, 700 years ago) was a tumultuous era, during which more than eleven major Ice Ages occurred! The Pleistocene is also the time when our earliest Homo Sapiens ancestors exited from Africa, invented the first tools and art forms, began refining spoken language and came to dominate over other animals like the Mammoth, which eventually became extinct. It was hard living in the Pleistocene because it was really cold!

The Holocene (11, 700 years ago until about 1800 AD) was a time that was much smoother than the Pleistocene in terms of climate change. At the end of the last Ice Age about 12,000 years ago, a more stable climate settled on the Earth. As the ice gave way to temperate climates, human populations spread to all continents of the Earth. Over several thousand years of relatively steady climates, agriculture  began to flourish in the Fertile Crescent and elsewhere in Africa, China, New Guinea and South America. Civilisations also began to rise and fall, as human populations grew along with cultural, scientific and technological innovations.

The Anthropocene is said to have began in the early to mid 1800s, with the rise of industrialisation. The invention of the steam engine in the 1700s meant that factories were built to mass-produce food and other goods that could be supplied by railroad. From the mid 1900s until today, we can see what is called the Great Acceleration of human enterprise on the Earth. Click on the graphs below for a closer look:

great accelaration

Because of this incredible growth in human population and consumption,  the use of fossil fuels like oil, coal and gas has continued to skyrocket. The emissions caused by burning these fuels is linked to significant changes in the Earth’s climate, particularly those associated with global warming,  sea level rises and storm intensity. Watch the video below to learn more about climate change in the Anthropocene era:

Unfortunately, the Great Acceleration of human consumption is also contributing to the mass extinction of plant and animal species living in the Earth’s biosphere. This is often due to the loss of habitats which support the diversity of life on Earth, such as rainforests, wetlands and reef systems. The following video describes how the Earth’s water cycles are being affected in the Anthropocene:

The last video called for creative solutions to address the Earth’s changing water cycles of the Anthropocene. Can you think of some ideas that could help save more clean water for the plants, animals and people who need it the most?

While there continues to be some disagreement among scientists about the scale of humanity’s impact on the Earth, this research project is about what kids and teenagers in our communities think and feel about climate change. Do you think we’re living in a new  era in which humans are shaping the Earth and its global cycles? Do human-induced environmental changes mean that we should change how we live every day?  Or should we just continue on conducting ‘business as usual’?

By becoming part of this program of research you have a unique opportunity to learn  what the people around you think and feel about climate change. Whatever you discover about climate change in your community, your work will make a difference in how we understand and respond to the changing world we live in today.

NEXT: Learn About The Project