Why weather

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Credit: NOAA. They zip around our planet from pole to pole 14 times per day. Because they orbit while the Earth is rotating below, these satellites can see every part of Earth twice each day. By watching these global weather patterns, polar orbiting satellites can help meteorologists accurately predict long-term forecasts—up to 7 days in the future.

Polar orbiting satellites get a complete view of Earth each day by orbiting from pole to pole. Because the Earth spins, the satellite sees a different part of Earth with each orbit. The outcome from the models is also separately studied by a team of scientists to verify and authenticate its results. But the art of weather prediction or interpretation is consistently evolving, with many new strategically important indicators being added to the variables.

Sea surface temperature monitoring remains a critical element. ENSO El Nino-Southern Oscillation factor, which is a recurring climate pattern, involving changes in the temperature of waters in the central and eastern tropical Pacific Ocean. This oscillating warming and cooling pattern, referred to as the ENSO cycle, directly affects rainfall distribution in the tropics and can have a strong influence on weather across the United States and other parts of the world.

So what has changed in the recent years that is causing Indian Monsoon to become harder to predict? In fact, in the last four years alone, we have seen the formation of four severe cyclones in the region. The recent cyclone Tauktae which formed on May 14 this year , for instance, took only two days to develop into a severe cyclone, while others in contrast have been much slower.

Today sea surface temperatures over the Arabian Sea are on the rise and it has been producing conducive wind shears, which in turn, support these cyclones. These cyclones are known to interfere with the weather systems and wind movements generated by the high pressure area near the Mascarene Islands which provides a source to the winds flowing from the south west direction into India and carrying the moisture laden clouds to the Indian shores.

Why is this happening Climate change and global warming seems to be the most logical answer. Analysis done recently by the Potsdam Institute for Climate Impact Research, which compared more than 30 climate models from all around the world, found that for every degree of Celsius warming, monsoon rainfalls increase by about five per cent.

Since the s, changes made in the name of human progress began to overtake the slow natural changes which occur over many millennia. The greenhouse gas-induced warming has now become the deciding driver for a more erratic monsoon season. Another study on variability in the Mascarene High conducted by the National Centre for Polar and Ocean Research has revealed that the region experienced significantly increased sea surface temperatures during the global warming hiatus This warming of the sea surface temperatures, according to the study, resulted in a decrease in pressure gradient between Mascarene High Pressure Area and the Indian landmass, which in turn suppressed the intensity of low-level cross equatorial winds over the western Indian Ocean, affecting the onset of the monsoon over the Indian subcontinent.

The Mascarene Islands is a group of islands in the Indian Ocean, east of Madagascar, from where the cross equatorial winds blow to India. This area near the Mascarene islands is a high-pressure-zone that drives the winds towards Somalia, which are then deflected towards the Indian Peninsula carrying the moisture laden clouds with them. Atmospheric pressure changes as air becomes warmer or colder, because the temperature of air affects how dense it is. Warm air molecules have more energy and move further apart, meaning that warm air is less dense than cold air.

Atmospheric pressure also decreases as you move higher into the atmosphere. Imagine the atmosphere as a huge ocean of air that we live underneath. High-pressure weather systems tend to bring cooler temperatures and clear skies. On the other hand, low-pressure weather systems bring warm temperatures and more unsettled weather. Clouds are visible masses of water vapour in our atmosphere.

They are formed when water evaporates from places like oceans and lakes, and then condenses when it cools down again. Wind is the movement of air in the sky.

Wind is caused by the different air pressures in our atmosphere.