How does black carbon affect monsoons?

BENGALURU: Black carbon aerosols (similar to soot) have reduced rainfall in south India during the pre-monsoon season. Research has indicated that elevated heating, due to black carbon aerosols during pre-monsoon, causes enhanced rain over the north-east and some parts of central India but reduction of rain over south.

How do aerosols affect monsoons?

Thus, the presence of high amounts of aerosols during the monsoon months lead to the formation of taller clouds with a large number of ice particles and, eventually, heavier rainfall. The researchers of the current study, in their analysis of the satellite data, found that such a phenomenon occurred over central India.

Does black carbon aerosols have a warming effect?

Black carbon (BC) aerosols, unlike most of the atmospheric aerosols, absorb solar radiation and thus have a warming effect on the planet. This warming effect contrasts with the cooling effect of other aerosols that are primarily scattering (e.g. sulfate aerosols).

What are the factors affecting Indian monsoon?

Factors influencing the onset of SW monsoons:

• Intense low-pressure formation over the Tibetan Plateau.
• The permanent high-pressure cell in the South of the Indian Ocean.
• Subtropical jet stream.
• African Easterly jet (Tropical easterly jet)
• Inter-Tropical Convergence Zone (ITCZ)

How does black carbon disrupt cloudiness?

If black carbon heats up the layer of the atmosphere where clouds are forming, for example, they will evaporate. They can no longer reflect sunlight back into space, and so the soot-laced clouds end up warming the atmosphere. These clouds are like shields, blocking incoming sunlight.

What is black carbon and how does it cause global warming?

Black carbon is generally thought to have both a direct warming effect (by absorbing incoming solar radiation in the atmosphere and converting it to heat radiation) and an indirect warming effect (by reducing the reflectivity of snow and ice).

What is aerosol made of science?

An aerosol is a suspension of fine solid particles or liquid droplets in air or another gas. Aerosols can be natural or anthropogenic. Examples of natural aerosols are fog or mist, dust, forest exudates, and geyser steam.

What causes break in monsoon?

Explain the reasons why break in monsoon occurs – When tropical disturbances advance along the monsoon trough, sometimes the sea level low pressure area weakens and making the low pressure area from 900 mb to 700 mb height to move north of the trough. This is how a monsoon break works.

What are the factors affecting for the formation of monsoon wind?

The primary cause of monsoons is the difference between annual temperature trends over land and sea. The apparent position of the Sun with reference to the Earth oscillates from the Tropic of Cancer to the Tropic of Capricorn. Thus the low pressure region created by solar heating also changes latitude.

What is the source of black carbon aerosols?

Black carbon (BC) aerosol, often called soot, is the dominant form of light absorbing particulate matter in the atmosphere. BC is emitted by incomplete combustion processes, both human (e.g., diesel engines) and natural (e.g., wildfire).

How does black carbon affect the monsoon in Asia?

Modeling studies have shown that that black carbon (BC) aerosols can affect the monsoons of Asia (e.g., Menon et al. 2002; Ramanathan et al. 2005). These BC aerosols make up a significant part of what has been called the atmospheric brown cloud (ABC) over Asia (Ramanathan and Crutzen 2003).

How does BC aerosols affect the Indian monsoon?

With the onset of the monsoon, the reduced surface temperatures in the Bay of Bengal, Arabian Sea, and over India that extend to the Himalayas act to reduce monsoon rainfall over India itself, with some small increases over the Tibetan Plateau. Precipitation over China generally decreases due to the BC aerosol effects.

Why are BC aerosols important to South Asia?

The BC aerosols act to increase lower-tropospheric heating over South Asia and reduce the amount of solar radiation reaching the surface during the dry season, as noted in previous studies.

What makes up the Black Cloud over Asia?

These BC aerosols make up a significant part of what has been called the atmospheric brown cloud (ABC) over Asia (Ramanathan and Crutzen 2003). The black carbon considered in this study represents the soot produced by fossil fuel combustion and biomass burning (Collins et al. 2002).