Understanding the Montreal Protocol and Environmental Issues

The question asks about the primary environmental issue that the Montreal Protocol was designed to combat. This is a key international treaty focusing on protecting the Earth's atmosphere.

Analyzing the Montreal Protocol

The Montreal Protocol on Substances that Deplete the Ozone Layer is an international treaty signed in 1987. Its main objective was to protect the ozone layer by phasing out the production and consumption of substances known to deplete it. These substances include chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), which were commonly used in refrigerants, aerosols, and foam blowing.

Connecting the Montreal Protocol to the Answer

Based on its objective, the Montreal Protocol was specifically created to address the problem of the thinning ozone layer, commonly referred to as ozone depletion. Scientific evidence showed that certain human-produced chemicals were causing significant damage to the stratospheric ozone layer, which absorbs most of the sun's harmful ultraviolet (UV) radiation.

Evaluating the Given Options

Let's examine each option provided:

• Ozone depletion: As discussed, the Montreal Protocol was explicitly designed to phase out substances that deplete the ozone layer. This aligns directly with the protocol's purpose.
• Sound pollution: Sound pollution, or excessive and disruptive noise, is an environmental issue related to human health and well-being but is completely unrelated to atmospheric chemistry or international agreements like the Montreal Protocol.
• Greenhouse gas emissions: Greenhouse gas emissions, such as carbon dioxide and methane, are the primary drivers of climate change and global warming. While some ozone-depleting substances are also potent greenhouse gases, the Montreal Protocol's main focus and legal framework were on ozone depletion, not climate change. Other agreements like the Kyoto Protocol and the Paris Agreement specifically target greenhouse gas emissions.
• Water pollution: Water pollution refers to the contamination of bodies of water. This is a crucial environmental issue, but it is unrelated to the atmospheric concerns addressed by the Montreal Protocol.

Conclusion on the Montreal Protocol's Target Issue

Considering the stated purpose and the substances regulated by the treaty, the Montreal Protocol was signed to combat ozone depletion.

Revision Table: Montreal Protocol Key Facts

Additional Information on Ozone Layer Protection

The Montreal Protocol is widely considered one of the most successful international environmental treaties. The global effort to phase out ozone-depleting substances has led to a significant reduction in their atmospheric concentrations. Scientists have observed a recovery of the ozone layer, and it is expected to return to 1980 levels by the middle of the 21st century over most latitudes, and later over the polar regions.

The success of the Montreal Protocol demonstrates that international cooperation can be effective in addressing global environmental problems.