Earth's Natural Wonders
Green Living
Earth's Ecosystems
Climate Change
Reduce, Reuse, Recycle
100
This is the world's largest coral reef system, located off the coast of Australia.
Great Barrier Reef
100
This reusable item can replace plastic water bottles.
Reusable water bottle
100
This is the largest tropical rainforest in the world
Amazon Rainforest
100
This gas, produced by burning fossil fuels, is a major contributor to global warming.
Carbon dioxide (CO2)
100
This symbol, consisting of three arrows forming a triangle, represents recycling.
Recycling symbol (Mobius loop)
200
This African waterfall, one of the largest in the world, is known as "the smoke that thunders."
Victoria Falls
200
This mode of transportation is eco-friendly and good exercise.
Bicycle
200
This cold, treeless biome is found in the Arctic.
Tundra
200
This layer of the atmosphere protects Earth from harmful UV radiation.
Ozone layer
200
This type of waste can be composted to create nutrient-rich soil.
Organic waste
300
This colorful hot spring in Yellowstone National Park is named after a rainbow.
Grand Prismatic Spring
300
This type of gardening involves growing plants on rooftops.
Rooftop gardening
300
This term describes the variety of plant and animal life in a particular habitat.
Biodiversity
300
This international agreement aims to combat climate change and was adopted in 2015.
Paris Agreement
300
This color of recycling bin is typically used for paper products.
Blue
400
This cave system in Vietnam is home to the world's largest known cave passage.
Son Doong Cave
400
This term refers to food grown without synthetic pesticides or fertilizers.
Organic
400
This type of wetland ecosystem is characterized by grasses, rushes, and reeds.
Marsh
400
This renewable energy source harnesses the power of flowing water to generate electricity.
Hydroelectric power
400
This term describes the practice of reusing water for different purposes.
Water recycling
500
This natural phenomenon in Venezuela is the world's largest and longest-lasting lightning storm.
Catatumbo Lightning
500
This renewable energy source harnesses the power of the Earth's internal heat to generate electricity and provide heating.
What is geothermal energy?
500
This zone in the ocean where sunlight penetrates is called the _ zone.
Photic zone
500
This greenhouse gas, with the chemical formula CH4, is about 25 times more potent than carbon dioxide in trapping heat in the atmosphere over a 100-year period.
Methane
500
This term describes the process of breaking down plastic into its chemical components for reuse in new plastic products.
Chemical recycling
