Evidence for Climate Change

Scientists determine climate conditions today by...

• Making direct measurements.

• Creating computer models.

• Examining ice cores.

• Using dendrochronology.

To learn what climates were like in the past, scientists investigate the following types of evidence that serve as substitutes for direct measurement.

• Computer models

• Proxy indicators

• Topography

• Carbon footprints

Scientists can extract samples of ancient air from ice cores

• True
• False

How do scientists collect evidence about climate?  

• using remote sensing from space with satellites
• by ground-based measurements of surface temperatures, carbon dioxide concentration and sea level
• by collecting “proxy data” from tree rings, ice cores, and historical records
• all of the above

Studying tree rings is a way of gathering evidence for climate change. This is called _______________.

• Biology

• Dendrochronology

• Ice Sheet Retreat

• Sunspot Cycles

By examining ice cores, we know that when carbon dioxide levels are high, temperatures are also higher.

• True

• False

Thicker tree rings indicate poor growing conditions for plants and trees.

• True

• False

What source of evidence for climate change is shown in the image?

• Ice Cores

• Pollen Analysis

• Glacier Retreat

• Dendrochronology

How can monitoring glaciers provide evidence for climate change?

• When climate gets warmer, glaciers get larger.

• When glaciers retreat it means that it is getting colder.

• Glaciers contain old thermometers to measure temperatures.

• When climate is warmer, glaciers retreat. When climate is colder, glaciers expand and get larger.

Which of the following is the best conclusion that can be made from this graph?

• atmospheric carbon dioxide levels have been decreasing since 1960
• Hawaii has a lot of carbon dioxide
• humans have been working hard to decrease carbon dioxide levels
• atmospheric carbon dioxide levels have increased steadily since 1960