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What's the difference between weather and climate?

Graph Some people say "weather is what you get" and "climate is what you expect." "Weather" refers to the more local changes in the climate we see around us, on short timescales from minutes to hours to days to weeks. Examples are familiar - rain, snow, clouds, winds, thunderstorms, heat waves and floods. "Climate" refers to longer-term averages (they may be regional or global), and can be thought of as the weather averaged over several seasons, years or decades.

If all of Earth's ice melts and flows into the ocean, what would happen to the planet's rotation?

The Earth rotates about its axis once a day, but it does not do so uniformly. Instead, the rate of rotation varies by up to a millisecond per day. Like a spinning ice skater whose speed of rotation increases as the skater's arms are brought closer to their body, the speed of the Earth's rotation will increase if its mass is brought closer to its axis of rotation.

Is the sun causing global warming?

Graph No. The sun can influence the Earth's climate, but it isn't responsible for the warming trend we've seen over the past few decades. The sun is a giver of life; it helps keep the planet warm enough for us to survive. We know subtle changes in the Earth's orbit around the sun are responsible for the comings and goings of the ice ages.

Is it too late to prevent climate change?

Humans have caused major climate changes to happen already, and we have set in motion more changes still. Even if we stopped emitting greenhouse gases today, global warming would continue to happen for at least several more decades if not centuries. That's because it takes a while for the planet (for example, the oceans) to respond, and because carbon dioxide - the predominant heat-trapping gas - lingers in the atmosphere for hundreds of years. There is a time lag between what we do and when we feel it.

Is the ozone hole causing climate change?

Graph Yes and no. The ozone hole is basically a man-made hole in the ozone layer above the South Pole during the Southern Hemisphere's spring. The ozone layer, which lies high up in the atmosphere, shields us from harmful ultraviolet (UV) rays that come from the sun. Unfortunately we punched a hole in it, through the use of gases like chlorofluorocarbons (CFCs) in spray cans and refrigerants, which break down ozone molecules in the upper atmosphere.

What is climate change?

Climate change is a change in the usual weather found in a place. This could be a change in how much rain a place usually gets in a year. Or it could be a change in a place's usual temperature for a month or season. Climate change is also a change in Earth's climate. This could be a change in Earth's usual temperature. Or it could be a change in where rain and snow usually fall on Earth.

Weather can change in just a few hours. Climate takes hundreds or even millions of years to change. Earth's climate is always changing. There have been times when Earth's climate has been warmer than it is now. There have been times when it has been cooler. These times can last thousands or millions of years.

Why is climate changing?

Graph The earth is surrounded by layer of gases that keep its surface warm and able to sustain life. Since industrialization, this layer has grown thicker due to increased commercial activities and pollution due to which the greenhouse gases have caused an increase in the average temperature in the atmosphere.

Greenhouse gases

Graph A greenhouse gas is any gaseous compound in the atmosphere that is capable of absorbing infrared radiation, thereby trapping and holding heat in the atmosphere. These gases have an effect similar to the glass roof of a greenhouse which allows the sun's rays to penetrate the atmosphere to heat the earth, but prevent the energy from being radiated back into space.

Climate change impact on india

Changes in average temperature, rainfall patterns and monsoon timings will affect India's entire environment, especially the nation's water resources, sea levels, and water diversity, impacting a wide range of sectors, particularly agriculture.