Changes in Climate

Uncover Earth's climate history! Learn how scientists study past climates and the causes of change.

What principle do scientists follow when they study ancient climates? List three sources of information scientists use to learn about ancient climates. Evidence of Climate Change Inner tree rings hold clues about a tree's early years. Outer rings hold clues about a tree's later years.Label the sections:Cool or dry climateWarm or wet climate Cool or dry climate Warm or wet climate How does Earth's surface change during an ice age? What are three possible causes of climate change? Fill in the Blank 1. Solid particles or liquid drops in gas, called aerosols, can stay in the upper atmosphere for months or years, reflecting away some incoming solar radiation.2. Dark, cooler regions on the surface of the sun, called sunspots, have been linked to short-term climate change.3. Over thousands of years, warm climate periods have alternated with cold climate periods known as ice ages, or glacial episodes.4. The movements of continents over time affected the global patterns of winds and ocean currents, which slowly changed climates.5. Major volcanic eruptions are one explanation for major climate changes.6. Scientists analyze pollen found in lake bottoms to learn what type of plants lived there thousands of years ago.7. The width of tree rings helps scientists learn about temperatures and precipitation long ago.8. Changes in the direction of Earth's axis and changes in the angle at which it tilts affect the severity of ice ages. Sort the Statements into True and False *2 True and 3 False* True Scientists believe that if plants or animals today need certain conditions to live, then similar plants and animals in the past also required those conditions. Changes in climate occur slowly,but the consequences of such changes are great. False During each ice age, huge sheets of ice calledaerosolscovered large parts of Earth's surface. Earth's climatehas not been affectedby the angle of Earth's axis and the shape of Earth's elliptical orbit around the sun. Scientists have concluded that there have been about five ice ages on Earth during the last "two million" years, the last ending about 10,000 years ago. At the end of the ice age, about 10,000 years ago, the land bridge disappeared into the sea. Describe how you think the land bridge had originally formed. Many animal species, such as mammoths and scimitar-toothed cats, became extinct at the end of the last ice age. Explain why this occurred. Scientists have evidence that people who crossed the land bridge migrated to all parts of North and South America. Choose one site in North America to which people might have migrated.1. Choose a location in North America.2. Assume that the climate at this location changed after the ice age to its current climate conditions.3. Describe how people there might have adapted to these climate changes.