Science Unit 3 Lesson 1 Flashcards
What was the Great Oxygenation Event?
Aquatic bacteria known as cyanobacteria developed the ability to photosynthesize roughly 2.3 billion years ago. By taking in carbon dioxide and releasing oxygen during photosynthesis, cyanobacteria changed the composition of the atmosphere. This addition of oxygen gas occurred over the course of hundreds of millions of years, as part of what is known as the Great Oxygenation Event.
What are the effects of the Great Oxygenation Event?
Earth’s atmosphere had been rich in methane, which is a potent heat-trapping molecule, or greenhouse gas. As oxygen displaced the methane in the atmosphere, Earth’s temperature dropped, leading to the longest glaciation period on record. The addition of oxygen also killed off most other life forms at the time, which were mainly anaerobic bacteria. This set the stage for the evolution of oxygen-breathing life forms.
What is feedback in science?
Feedback is the ablity of change in a system to lead to further changes
What is evidence for early climate change?
Air bubbles and particles trapped in the ice provide evidence of the conditions of the atmosphere long ago.This rust fell to the ocean floor, leaving evidence that scientists can study in sedimentary rock.
What does anaerobic mean?
anaerobic, meaning they could not use oxygen.
What is the span that th’s orbit changes from nearly circular to slightly oval on a blank-year cycle.
100,000 year cycle
Earth rotates on its axis at a tilt, which varies between a 22- and 24-degree tilt every 41,000 years.
idk just remember this pls
The axis also wobbles like a spinning toy top, toward and away from the sun, about every 26,000 years.
The combination of which cycles in Earth has resulted in periodic changes in the distance of Earth from the sun and the angle of the sunlight hitting Earth.
The combination of these cycles in Earth’s orbit, tilt, and wobble has resulted in periodic changes in the distance of Earth from the sun and the angle of the sunlight hitting Earth.
What are the Milankovitch Cycles?
The combination of these cycles in Earth’s orbit, tilt, and wobble has resulted in periodic changes in the distance of Earth from the sun and the angle of the sunlight hitting Earth.The Milankovitch cycles are collective effects of changes in the Earth’s movements on its climate over thousands of years. The cycles are named after Serbian geophysicist and astronomer Milutin Milanković.
What impact do the Milankovitch cycles have?
The Milankovitch Cycles, have an impact on seasons and periodic cycles of change in temperature over a long period of time.
Scientists believe that the Milankovitch cycles explain what?
Scientists believe that the Milankovitch cycles explain why Earth’s climate has fluctuated between glacial periods and interglacial periods
What is the glacial period and what is accoisated with it?
The glacial period is a period in Earth’s history marked by prolonged low global temperature.The periods of low temperature led to higher rates of glacier formation, which meant that sea levels were lower. Colder water is able to absorb more carbon dioxide, meaning that carbon dioxide levels in the atmosphere were lower during glacial periods and higher during interglacial periods
What is the interglacial period and what is it accoisated with?
The interglacial period is a period in Earth’s history marked by prolonged high global temperature. The interglacial periods resulted in the melting of glaciers and a rise in sea levels.
