Read the given passage and answer the following questions based on it.

Emissions of carbon dioxide and other greenhouse gases plunged 4.6 percent in 2020, as lockdowns in the first half of the year restricted global mobility and hampered economic activity. Many hoped that this would mark the beginning of a more permanent shift downwards in emissions. Emissions from the manufacturing and the energy sectors contributed the most to recent global increases based on updated information from the IMF’s Climate Change Indicators Dashboard —a joint effort among national and international statistical organizations to provide timely data to help monitor the transition to lower carbon use.

As greenhouse gas emissions from human activities increase, they build up in the atmosphere and warm the climate, leading to many other changes around the world —in the atmosphere, on land, and in the oceans. While total emissions have climbed significantly above pre-pandemic levels, increases from transportation and households were more muted last year as the pandemic weighed on global mobility. This was particularly evident with the emergence of the omicron variant in the fourth quarter of last year. The public health policy measures in many countries drove down the emissions of households and of the electricity sector.

It will be important to monitor the emissions of both of these sectors as economies fully reopen in the context of historically high fossil fuel-based energy prices. The Intergovernmental Panel on Climate Change has said that, in the scenarios they assessed, limiting atmospheric warming to the key level of around 1.5 degrees Celsius requires global greenhouse gas emissions to peak by 2025 at the latest, emphasizing that achieving this milestone is a crucial step towards controlling the severity of climate change. The new data from the climate dashboard underscore what some scientists have warned: time is running out, and we must urgently bend the emissions curve to achieve the necessary reductions to limit atmospheric warming.

What is the significance of limiting atmospheric warming to around 1.5 degrees Celsius, as mentioned by the IPCC?

The correct answer is: "It reduces the risk of severe climate impacts."

Let us carefully read and analyze the passage to understand why this is the correct answer and why all other options are incorrect.

Step 1: Locate the relevant portion of the passage.

The passage states: "The Intergovernmental Panel on Climate Change has said that, in the scenarios they assessed, limiting atmospheric warming to the key level of around 1.5 degrees Celsius requires global greenhouse gas emissions to peak by 2025 at the latest, emphasizing that achieving this milestone is a crucial step towards controlling the severity of climate change."

The key phrase here is "controlling the severity of climate change." This directly means reducing the risk of severe or catastrophic climate impacts — not eliminating all impacts entirely, but managing how severe they become.

Step 2: Understand what "controlling severity" means in context.

The passage also mentions that greenhouse gas emissions from human activities "build up in the atmosphere and warm the climate, leading to many other changes around the world — in the atmosphere, on land, and in the oceans." These changes represent the impacts of climate change. Limiting warming to 1.5°C is described as a way to control how bad these impacts get — in other words, to reduce the risk of severe climate impacts.

Step 3: Eliminate the incorrect options one by one.

Option 1 — "It prevents all climate-related changes."
This is too absolute. The passage does not say that limiting warming to 1.5°C will prevent all climate-related changes. It only says it controls the severity. Some level of change is already happening and will continue.

Option 2 — "It ensures immediate reductions in emissions."
This is incorrect. The passage says emissions need to peak by 2025 to achieve the 1.5°C target — this is a future goal, not an immediate guarantee of reductions.

Option 3 — "It avoids the need for future climate action."
This is the opposite of the passage's message. The passage explicitly states that "time is running out" and that we must "urgently bend the emissions curve," implying that continuous climate action is required.

Option 5 — "It guarantees economic growth."
The passage makes no mention whatsoever of any link between the 1.5°C target and economic growth. This is entirely unsupported.

Step 4: Confirm the correct answer.

The passage's language — "controlling the severity of climate change" — is a direct paraphrase of reducing the risk of severe climate impacts. This option is faithful to the text, neither overstating (like "prevents all changes") nor understating the significance of the 1.5°C milestone.

Therefore, the significance of limiting atmospheric warming to 1.5°C, as mentioned by the IPCC, is that it reduces the risk of severe climate impacts — making this the most accurate and well-supported answer based on the passage.