Madden julian oscillation and indian monsoon. Mjo.

The Madden–Julian oscillation is the largest element of the intraseasonal variability in the tropical atmosphere. It was discovered in 1971 by Roland Madden and Paul Julian of the American National Center for Atmospheric Research.

What is Mjo in geography?

The MJO can be defined as an eastward moving 'pulse' of clouds, rainfall, winds and pressure near the equator that typically recurs every 30 to 60 days. It's a traversing phenomenon and is most prominent over the Indian and Pacific Oceans.

What is the main source of intra seasonal climate variability in the tropics?

The Madden-Julian oscillation (MJO), sometimes known as the intraseasonal oscillation (ISO), is the leading mode of intraseasonal variability in the tropical climate system.

What causes the Madden-Julian Oscillation?

The wet phase of enhanced convection and precipitation is followed by a dry phase where thunderstorm activity is suppressed. Each cycle lasts approximately 30–60 days. Because of this pattern, the Madden–Julian oscillation is also known as the 30- to 60-day oscillation, 30- to 60-day wave, or intraseasonal oscillation.

How often does the Madden-Julian Oscillation occur?

The Madden-Julian Oscillation (MJO) is the major fluctuation in tropical weather on weekly to monthly timescales. The MJO can be characterised as an eastward moving 'pulse' of cloud and rainfall near the equator that typically recurs every 30 to 60 days.

What is Madden-Julian Oscillation Upsc?

According to India Met Department (IMD), the Arabian Sea arm of south-west monsoon is counting on an itinerant Madden-Julian Oscillation (MJO) wave for normal monsoon. ... The MJO can be defined as an eastward moving 'pulse' of clouds, rainfall, winds and pressure near the equator that typically recurs every 30 to 60 days.

Where is the Madden-Julian Oscillation?

northern Australia

The Madden-Julian Oscillation is moving over northern Australia, encouraging wet conditions. The climate driver usually takes between a month and 60 days to make its way around the tropics. Although this MJO is weak with the La Niña active, it opens the door for rain and storms in the coming weeks.

Why does Indian Ocean have dipole?

The Indian Ocean Dipole (IOD), also known as the Indian Niño, is an irregular oscillation of sea surface temperatures in which the western Indian Ocean becomes alternately warmer (positive phase) and then colder (negative phase) than the eastern part of the ocean.

What is MJO wave?

The MJO is a system of very tall or deep convective clouds (storminess) that travels eastward along the tropical Indian and Pacific Oceans approximately every 30-60 days. The convective region of the MJO has enhanced storms and rainfall, and it is usually sandwiched to the east and west by dry, sunny areas.

What is suppressed convection?

In the suppressed convective phase, winds converge at the top of the atmosphere, forcing air to sink and, later, to diverge at the surface (Rui and Wang, 1990). As air sinks from high altitudes, it warms and dries, which suppresses rainfall.

Where does the MJO start?

Indian Ocean

from Rol Madden and Paul Julian. Typically the convectively active stage of an MJO starts over the equatorial Indian Ocean and moves slowly eastward at 3-5 m/s toward the west and central Pacific Ocean.

Vineesh V
Assistant Professor of Geography,
Government College Chittur, Palakkad
Government of Kerala.

https://vineesh-geography.business.site

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