Global Temperature Rise — Reading Comprehension

Earth’s average temperature is not constant. Over the past 140 years, scientists have noticed a clear trend: the planet is getting warmer. This is not just a guess or a feeling—it is measured and recorded. Careful observations show that, since the late 1800s, global average temperature has risen by about 1.1°C (2°F). Most of this warming has taken place since 1980, making the last two decades the warmest years on record. Understanding this trend is important for predicting future climate and preparing for its impacts.

How Scientists Measure Temperature

Scientists use many methods to track changes in Earth’s temperature. The most direct way is with thermometers at weather stations around the world. These thermometers have been collecting daily measurements since the late 1800s, providing a long-term record. However, thermometers only measure the air at specific locations. To get a global picture, scientists also use satellites that measure temperatures from space and buoys that float in the oceans. Ships also collect data as they travel. By combining all these sources—thousands of weather stations, satellites, ships, and buoys—scientists can calculate Earth’s average temperature with a high degree of accuracy. Multiple independent scientific groups analyze the data separately, but they all find the same warming trend. This agreement increases confidence in the results.

Not Just Air: Oceans and Urban Effects

About 90% of the extra heat trapped by the planet goes into the oceans. This is because water absorbs heat more effectively than air. Ocean temperatures have risen alongside air temperatures, which scientists confirm with thermometer and buoy data. As a result, marine heatwaves have become more common. Scientists also account for the urban heat island effect, which means cities are often warmer than surrounding areas due to concrete and asphalt. To avoid bias, they adjust their data to make sure warming trends are not just due to cities. This careful process ensures that the measured warming reflects changes across the entire planet, not just urban areas.

Effects and Implications of Rising Temperatures

Rising global temperatures have many consequences. Heatwaves are becoming more frequent and intense, while cold snaps are less common. These changes affect ecosystems, weather patterns, and human health. The warming of the oceans can harm coral reefs and disrupt marine life. Understanding temperature records allows scientists to predict future climate changes and helps societies prepare for extreme weather events. Reliable temperature data is essential for developing policies to reduce greenhouse gas emissions and protect the environment.

Temperature records show the importance of scientific observation, careful measurement, and global cooperation. By understanding how and why the planet is warming, people can make informed choices about the future.

Interesting Fact: The ten warmest years ever recorded have all occurred since 2010, showing how rapidly the planet is changing.

What is the main trend shown by temperature records since the late 1800s?

About how much has Earth’s average temperature increased since pre-industrial times?

Which tool is NOT used to measure Earth’s temperature?

What is the urban heat island effect?

What is a marine heatwave?

What does the passage suggest is the main cause of the recent warming trend?

Why do scientists use multiple sources of temperature data?

True or False: Most of Earth's extra heat is absorbed by the oceans.

True or False: Only one group of scientists studies temperature records.

Which of these is a consequence of rising global temperatures, according to the passage?