The Kyoto Protocol has achieved only limited success in slowing the rise in atmospheric concentrations of greenhouse gases. , ,  Similarly, although the Law of the Sea Convention established the maritime rights of states, it has not been as effective in protecting the marine environment. The Montreal Protocol, in contrast, has successfully curtailed production and consumption of ozone-depleting substances and has begun to reverse the loss of atmospheric ozone. The following sections contrast these treaties in terms of their history, scope and complexity, national self-interests, fairness, and enforcement.
The Law of the Sea Convention addressed long-standing problems for which an extensive body of customary international law already existed, but still, negotiators labored for more than two decades before it entered into force. By contrast, stratospheric ozone depletion and global climate change are recent issues. Scientific evidence about the role of chlorofluorocarbons (CFCs) in ozone depletion was first obtained in the 1970s,  negotiations about ozone depletion began among 28 states in 1985, and the Montreal Protocol entered into force in 1989. Scientists reached a consensus about global climate change and the role of human activities in the 1980s. Many states convened in 1997 to negotiate the Kyoto Protocol, and it entered into force in 2005.
Scope and Complexity
The Law of the Sea Convention delineated territorial waters and extraction of natural resources from the seas and seabed—matters broad in scope but conceptually straightforward. The Montreal Protocol focused on human production and consumption of the few manufactured substances that deplete ozone; ozone depletion is associated with higher incidence of human skin cancer, a harm that is both significant and easily envisioned.  The Kyoto Protocol addressed the interactions between greenhouse gases and Earth’s climate, a much more difficult task because many natural and human activities generate greenhouse gases, and greenhouse gases are only one of many factors responsible for changes in climate.
The Law of the Sea Convention appealed to the self-interest of most states because it clarified territorial claims to natural resources and rights of passage. Matters of self-interest with respect to the protection of marine life in international waters are less obvious, and achieving this objective has proved more difficult.
The Montreal Protocol was consistent with the interests of several states, particularly, the United States.  By 1977, American consumers had become so worried about the loss of ozone in the upper atmosphere that they had reduced the U.S. market for ozone-depleting substances in spray cans by two-thirds, even without governmental regulation. The following year, U.S. legislation banned CFCs as propellants for nonessential uses. By 1987, the year in which the Montreal Protocol was drafted, U.S. production of ozone depleting substances had plummeted from one-half of the world’s total to a one-fourth.
In contrast, the Kyoto Protocol served the self-interests of few, if any, major world powers. On March 13, 2001, less than two months after he was sworn into office, President George W. Bush declared that he opposed the Kyoto Protocol because it “would cause serious harm to the U.S. economy.” 
The Law of the Sea Convention established uniform rules for territorial claims. The Montreal Protocol set standard limits to production and consumption of ozone-depleting substances, although it allotted developing states more time to meet these limits. The Kyoto Protocol, however, placed the burdens of compliance entirely on developed states, while it offered developing states financial benefits with few obligations.
Incidents of noncompliance with the Law of the Sea Convention, because they usually involve territorial rights, can quickly escalate. The treaty provided a mechanism for states to avoid armed conflict. Enforcement in the Montreal Protocol and the Kyoto Protocol provided incentives for compliance rather than sanctions for noncompliance. Incentives in the Montreal Protocol were adequate to compensate for abandoning ozone-depleting substances, particularly when alternative substances became available at modest costs, whereas incentives in the Kyoto Protocol did not at all compensate for most of the costs in mitigating greenhouse gas emissions. In both the Montreal Protocol and the Kyoto Protocol, sanctions for noncompliance do not compel states to honor their commitments.
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This is an excerpt from the book Global Climate Change: Convergence of Disciplines by Dr. Arnold J. Bloom and taken from UCVerse of the University of California.
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