Currently, the main challenge is that the long-term, financially viable, widely available and environmentally safe alternative technologies are still under development in many fields. The research and development are fast but deadlines for compliance are also pressing.

The Montreal Protocol on Substances that Deplete the Ozone Layer has since been recognized as an extraordinary environmental success in global cooperation to protect the ozone layer. The Montreal Protocol has completed more than 20 years of its progress.

Scientists who study the depletion of Earth

When nations made plans to save the ozone layer, they didn't factor in global warming. Quirin Schiermeier reports on how two environmental problems complicate each other.

Twenty years on, the success of the Montreal Protocol can help inform plans to mitigate climate change. (Editorial)

The issues of ozone depletion and climate change have been at the forefront of the international community

The Montreal Protocol has been extremely successful in
enabling the phase-out of ozone depleting substances (ODS).
As a result of these phase-outs, hydrofluorocarbons (HFCs) have
been commercialized as substitutes for ODS. The HFCs being used
as ODS substitutes are powerful greenhouse gases (GHG) with
global-warming potentials (GWP) hundreds to thousands of times

Film>> Ozone Killers

With advent of technologies our globe has become a `global village' . With its growth the present world is now facing a major problem of Global Warming. Unrestricted use of fossil fuels has increased the concentrations of green house gases (GHGs) like carbon dioxide to unprecedented levels, which the natural sinks in the bio-chemical cycles are finding too much to mitigate.

Bhutan will start phasing out hydro-chlorofluorocarbons (HCFC), an ozone depleting substance (ODS), starting 2013.