Thursday, September 10, 2009

Chennai - Avg. rainfall from Jun to Sep is 432mm, but we have got only 147.4mm... this is a shortfall of 64%
Chennai - Today's temperature came close to this record .. 38.9 C (19.9.1883)
Good news:: Delhi has received a total of 538.6 mm of rain this monsoon against an average of 573 mm.
Heavy rains lashed the national capital since last night, city received 93.2 mm of rains since 8:30 pm last night. This might be last shower.
Nine die in rain and flood related incidents ..

Indian South west monsoon and Global warming

South west monsoon is considered India’s lifeline. This brings rains across the country during the summer. But the geologist says, India may lose this lifeline in the span of 150 years. Researchers related to the events, have predicted this phenomenon is due to the fall out of the global warming. It has become responsible in increasing the rate of temperature rise over Arabian Sea.

In a very shocking revelation, the new study by Indian Institute of Tropical Meteorology warns that there is every likelihood of reducing the temperature difference between land and sea, commonly known as Temperature Gradient, accountable for attracting rain causing winds from Arabian Sea towards Indian mainland.

Global warming is the increase in the average temperature of the Earth’s near-surface air and oceans since the mide-20th century and its projected continuation. Global surface temperature increased 0.74 or 0.18C during the previous century.

The usually talked about measures of global warming happens to be the trend in globally averaged temperature closer to Earth’s surface. Expressed as linear trend, this temperature rose by 0.74C or 0.18C over the period 1006-2005. The rate of warming over the last 50 years of that period was almost double. The urban heat island effect is estimated to account for about 0.002C of warming per decade since 1900.

As per NASA’s Goddard Institute for Space Studies, 2005 it was the warmest year since reliable, widespread instrumental measurements became available in the late 1800s exceeding the previous record set in 1998 by a few hundredths of a degree.

The study says, if the gradient turns out to be zero, the monsoon winds will be replaced by easterly winds thus disturbing the flow of South-west monsoon. The Indian Meteorology Department demonstrated a 23 per cent reduced rain during the present season is a great point of alarming .At a time when the entire world is discussing about the climate and global warming, India has to prepare a well placed mechanism to meet any forthcoming eventuality. And this can be an indication of this phenomenon.

More than anything else, global warming is responsible for the rise in the average temperature across the globe. This is considered behind the rise in temperature over the Arabian Sea, and confirms the study.

Withdrawal of monsoon delayed by another week

he presence of a cyclonic circulation over Madhya Pradesh has delayed the withdrawal of monsoon from the country by another week.

According to the statistics of the India Meteorological Department (IMD), the monsoon starts it's withdrawal from Rajasthan around September 1. But this year, there have been no signs of the monsoon receding.

"Before we declare the withdrawal of the monsoon, we look for certain weather conditions, like dry conditions must prevail in the state for over five days and the level of humidity should go down. If those conditions are not available then a withdrawal can not be declared," said Medha Khole, Director (Weather Forecasting ), India Meteorological Department (IMD).

Currently, Rajasthan, from where we normally start giving withdrawal, is not showing any of these favourable conditions, Khole said, adding that the weather conditions are expected to remain the same for the next one week.

"There is a cyclonic circulation present near Madhya Pradesh and it is likely to move towards Rajasthan. This movement will result cause rainfall in Rajasthan for the next few of days. So the withdrawal is not expected for next two days and five days after. This makes it a total of seven days i.e. one week," she said.

Meanwhile, this delay of withdrawal may bring some good news for farmers, feels R P Samui, deputy director general meteorology, IMD. "This delay in the monsoon's return journey means more rainfall in certain areas for some more time. It would certainly prove to be beneficial for farmers in some areas," Samui said.

Samui opined that this delay of withdrawal would be advantageous for the standing crops and even for winter crops.
chennai - Going to be clear and very Hot.. around 38 deg
GFS predicts almost NO rain for 90% of India, except Andaman after 12-Sep-09 ..
MJO suggests that we are moving into DRY phase, it will last till 10-Oct-09, after this we can expect NE monsoon ..
Other than central India.. Whole of South-India is CLEAR after almost 2 months. .. Last remains of "03B" is stationery over central M.P, in fact it has moved slightly to east in past 18 hrs.