What causes Madden-Julian Oscillation?
What causes 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 does Madden-Julian Oscillation work?
It brings major fluctuation in tropical weather on weekly to monthly timescales. 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.
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.
Where is the Madden-Julian Oscillation?
The Madden-Julian Oscillation is characterised by an eastward spread of large regions of enhanced and suppressed tropical rainfall, mainly observed over the Indian and Pacific Ocean.
What is the 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 Intraseasonal oscillation?
The intraseasonal oscillation refers to variability on timescales of 20-100 days. This range of timescale is in between the typical timescales for weather (up to 15 days) and climate (from a season and beyond).
How long are MJO phases?
Each cycle lasts approximately 30–60 days. Because of this pattern, The MJO is also known as the 30–60 day oscillation, 30–60 day wave, or intraseasonal oscillation.
How does MJO affect ENSO?
Many observations have shown anomalously strong MJO activities prior to and during the onset of ENSO warm events (Fig. 1). Seasonal mean MJO activity tends to lead ENSO SST by 6 – 12 months (Zhang and Gottschalck 2002). Their strongest lag correlation occurs between the MJO in boreal spring and ENSO SST in winter.
What is El Nino Modoki?
El Niño Modoki is a coupled ocean-atmosphere phenomenon in the tropical Pacific. It is different from another coupled phenomenon in the tropical Pacific namely, El Niño. Conventional El Niño is characterized by strong anomalous warming in the eastern equatorial Pacific.
What is interannual variability?
The year-to-year fluctuation of the climate from its mean state is referred to as interannual variability, such as the deviation of precipitation and temperature at interannual timescale from the mean state.
What are some of the causes of Intraseasonal variations in the monsoon?
An influx of freshwater from the monsoon, the researchers found, creates a shallow mixed layer and a thick barrier layer, causing dramatic fluctuations in sea surface temperature over the course of the season.
What is the SOI index?
The Southern Oscillation Index (SOI) tracks the atmospheric part of the El Niño–La Niña climate pattern by comparing surface air pressure anomalies at Darwin, Australia, to pressure anomalies at Tahiti. The anomalies—departures from average conditions—indicate the strength of the Walker Circulation.