Story Guide

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[Target Audience: Upper elementary grades]

Quiz game!

Q1: At the 21st Conference of the Parties (COP21) to the United Nations Framework Convention on Climate Change (UNFCCC) in 2015, a total of 196 countries around the world agreed to work together to hold global temperature rise this century to well below 2 degrees Celsius. In which city was the meeting held?

1. Potsdam

2. Berlin

3. Paris


Q1: At the 21st Conference of the Parties (COP21) to the United Nations Framework Convention on Climate Change (UNFCCC) in 2015, a total of 196 countries around the world agreed to work together to hold global temperature rise this century to well below 2 degrees Celsius. In which city was the meeting held?

Answers:3. Paris

COP21 was held in Paris, France in 2015. This historical agreement, therefore, is called the Paris Agreement. France's outstanding handling of the conference is thought to have contributed to the agreement.
Treaties, declarations, and agreements are often named after the city where they were adopted. For example, the first international agreement on global warming (COP3) adopted in Kyoto, Japan in 1997 is called the Kyoto Protocol. Most of the 55 participating countries to the Protocol were advanced countries, but many developing countries were included among the 196 signatories of the Paris Agreement adopted 18 years after the Kyoto Protocol.
The commemorative first Conference of Parties (COP1) to the UNFCCC was held in Berlin, Germany. Angela Merkel, the then German Minister of the Environment who went on to become Prime Minister, served as the chairperson at COP1. Professor Schellnhuber also participated in the meeting.
The Potsdam Institute for Climate Impact Research (PIK), at which Professor Schellnhuber serves as Director, is located in Potsdam, Germany. It is a beautiful research institute surrounded by forests.

Q2: Choose the statement below that best expresses Professor Schellnhuber's idea about global warming measures:

Answers:2. To counter global warming before it's too late, we need to take measures now.

Professor Schellnhuber has researched phenomena caused by global warming, aspects that have become serious threats to humans. He also insists that there is no time to waste. In the past, measures against global warming were resisted because they interfered with economic growth. After the adoption of the Paris Agreement, however, many companies have come to see the fight against global warming as a chance to develop and sell new technologies and materials.
The early 1990s, when Professor Schellnhuber started his research, was when people started recognizing global warming as an issue. There had been some doubt that human activity was the cause; but, as studies on global warming progressed, it became increasingly clear that greenhouse gases discharged by humans were a significant factor (95%).
We have seen the impact of global warming around the globe; and while it may, for example, take hundreds of years for the glaciers in Greenland to melt away, we need to act now to prevent the disaster that will result when they do. Even if global warming isn't affecting us now, we must think about the world we will pass to our children and their children. It is the reason Professor Schellnhuber has worked so hard to identify problems and create measures to counter them.

Important Points!

Why are global warming measures necessary?

What kind of things would happen if global warming progresses at the current rate?

More Information!

One of the themes that Professor Schellnhuber has worked on in this research is the "tipping element." The tipping element means changes triggered by global warming, changes of enormous magnitude over broad areas.


This map shows a wide range of tipping elements that may occur on the earth. Since our story explains some of them, we describe the rest of the tipping elements here.

Melting ice and glaciers in the cryosphere

Ice and glaciers melt as the temperatures rise in regions covered with snow and ice, such areas as the Arctic and Antarctic, and mountainous areas.
Have you ever tried to burn blackened paper using a magnifying glass to focus the sunlight on it? The reason we use black paper is that dark colors tend to absorb sunlight more than light colors do.
If you have ever been to a snowfield on a sunny day, you know that it's hard to keep your eyes open. This is because the white snow and ice reflect most of the sunlight. However, as the black soil and rocks under the snow appear, or as the blue ocean under it appears, the sunlight is absorbed. In other words, once ice starts melting, a vicious cycle begins: the temperature increases, which increases the warming in the region, and this accelerates the melting of glaciers.

Loss of sea ice in the Arctic Ocean

Sea ice in the Arctic Ocean has decreased and become thinner, something that is more obvious in summer than winter. It has rapidly advanced over the past decades, and the sea ice in the Arctic Ocean may disappear in summer by the end of the 21st century.

Melting of glaciers around Greenland

See the text.

Melting of glaciers in the Antarctic

See the text.

Melting of permafrost

Permafrost is ground that remains frozen throughout the year. Cold regions at high altitudes or in areas with high latitude such as Siberia and Alaska have permafrost. The permafrost holds a tremendous amount of greenhouse gases, including CO2 and Methane, from the last glacial period about 10,000 years ago. If the permafrost melts, the greenhouse gases will get discharged into the air, which in turn will accelerate global warming further.

Methane from the ocean

Methane hydrate is a solid matter when frozen, but becomes a greenhouse gas when it thaws. It has accumulated at the bottom of the Arctic Ocean near eastern Siberia. Methane hydrate can maintain its solid state only under low temperature and high pressure. Therefore, once the water temperature of the deep sea increases, methane hydrate melts into a large amount of methane that seeps into the air. This would accelerate global warming significantly.

Changes in atmospheric and oceanic circulation systems

The atmospheric and oceanic circulation systems play a role in adjusting the earth's climate. The location and speed of the air flow and oceanic current are closely related to air and water temperatures. Therefore, any increase in air temperature due to global warming disturbs these systems.

Deceleration of deep ocean circulation

See the text.

El Nino-Southern Oscillation (ENSO)

The trade winds blowing from east to the west bring cold water from the ocean floor in the eastern Pacific Ocean around South America and bring warm sea water on the surface to the western Pacific Ocean around Indonesia. However, when the trade winds decrease and leave the warm sea water in the east- and mid-Pacific Ocean, the water temperature increases in the region for from a few months to a year. This phenomenon is named El Nino, which is responsible for abnormal weather all around the world. It occurs typically once every few years, but global warming has given rise to the scale and frequency of the El Nino Effect to increase.

Deceleration and stagnation of the jet stream

The jet stream is a westerly wind that blows at high speed about 10 km above the ground near the middle latitudes of the northern hemisphere. The speed increases when the difference in temperature between the Arctic and the equator increases. Global warming increases the temperature of the Arctic, which reduces the temperature difference and slows the jet stream. It causes a wide range of abnormal weather.

Instability of monsoons

Monsoons in India and the Indochinese Peninsula in summer are westerly wind blowing from the ocean. They are warm and wet and bring rain to the region. Global warming can affect the amount of rain to cause drought and flooding.

Impact of West African monsoons on the Sahara

West African monsoons blowing from the Gulf of Guinea bring rain to Africa. Although global warming may impact the amount of rain, the effect it may have is still unknown. Some predict that the amount of rain will decrease to cause drought in the Sahara Desert, especially in Sahel, which is located at the southern end of the desert, to become serious. However, it is also possible that the amount of rain will increase and make the Sahara Desert greener.
Greening sounds good. However, this may stop dust from the Sahara Desert from being carried to the continents of North and South America over the Atlantic Ocean, which would deprive the coral reefs in the Caribbean Sea and rainforests in the Amazon of precious nutrients.

Dry weather in the southwestern United States

The southwestern area of the United States is dry. A system very similar to monsoons also influences the area. If the amount of rain decreases, the dryness may become more serious.

Changes in ecosystems

If a region becomes hotter and drier due to global warming, plants and animals that have lived there may not be able to survive. Some may migrate to higher areas or closer to the Polar Regions; however, the organisms that already live in the Polar Regions will not have anywhere to go. Besides, forests play an important role in absorbing CO2, and the loss of this function may promote global warming.

Changes that may occur in the rainforests in Amazon

See the text.

A decrease of northern forests

Coniferous forests in Northern Europe and North America account for even one third of the world's forests. They have their own ecosystems and accumulate a large amount of CO2 in the ground. Forests close to Polar Regions tend to be more sensitive to temperature increase, and there are concerns about ecological destruction and CO2 emissions due to the loss of forests.

Whitening and extinction of coral reefs

See the text.

A weakening of the marine carbon pump

The ocean is the largest CO2 absorbent in nature, absorbing 40% of the CO2 discharged by humans. The absorbed CO2 is taken up by phytoplankton and sinks under the waves with the dead plankton. However, an excessive amount of CO2 emissions causes acidification and may degrade this function.

Professor Schellnhuber is
featured in Gring and Woodin's Comic!


Prof. Hans J. Schellnhuber