Earth Now is an application that visualizes recent global climate data from Earth Science satellites. The visualized data include surface air temperature, carbon dioxide, carbon monoxide, ozone, and water vapor, as well as gravity and sea-level variations.

The early Earth was very different from our Earth today. Earth’s first atmosphere had lots of water vapor but had almost no oxygen. Later, frequent volcanic eruptions put several different gases into the air (Figure 12.13). These gases created a new type of atmosphere for Earth.

Earth and its atmosphere are continuously altered. Plate tectonics shift the continents, raise mountains and move the ocean floor while processes not fully understood alter the climate. Such constant change has characterized Earth since its beginning some 4.5 billion years ago.

In Earth’s Beginning At its beginning, Earth was unrecognizable from its modern form. At first, it was extremely hot, to the point that the planet likely consisted almost entirely of molten magma. Over the course of a few hundred million years, the planet began to cool and oceans of liquid water formed.

There are many causes of environmental changes on Earth. Natural events cause changes in climate. For example, large volcanic eruptions release tiny particles into the atmosphere that block sunlight, resulting in surface cooling that lasts for a few years. Human activities can also change the environment.

The five direct drivers of the decline in nature are in order of importance (1) changes in land and sea use; (2) direct exploitation of organisms; (3) climate change; (4) pollution and (5) invasive alien species. Around 1 million plant and animal species are now threatened with extinction.

As the Earth moved out of ice ages over the past million years, the global temperature rose a total of 4 to 7 degrees Celsius over about 5,000 years. In the past century alone, the temperature has climbed 0.7 degrees Celsius, roughly ten times faster than the average rate of ice-age-recovery warming.

The earliest life forms we know of were microscopic organisms (microbes) that left signals of their presence in rocks about 3.7 billion years old. The signals consisted of a type of carbon molecule that is produced by living things.

The Past, Present, and Future Of Planet Earth. It is predicted that billions of years from now, the Earth will be destroyed by the Sun, thus ending all life on the planet. The future of our planet is a big mystery but according to some theories, the Earth might be destroyed by the Sun.

As the iron was used up at later stages, the oxygen was released and started building up in the Earth’s atmosphere. Soon, life dependent on oxygen began to evolve. For some time, about 650 million years ago, the Earth was completely covered in ice from the tropics to the poles.

During such bombardments, the comets, being bearers of water could have contributed much of the water in the oceans of the Earth. Early life flourished with the release of oxygen to the Earth’s atmosphere about 3.5 billion years ago as a result of cyanobacterial metabolism in the Earth’s oceans.

Soft-bodied creatures evolved in early Cambrian and those with hard shells evolved later. Though life continued to evolve and diversify on Earth, such periods of growth and evolution were interrupted by mass extinction events where many major forms of life on Earth got completely or partially wiped out, and many were newly formed.