Posts Tagged ‘precipitation’
India’s meteorological department has issued its second long range forecast for the 2011 monsoon and has lowered its estimate. Rainfall will be 95% of the 50-year average in the June-September season, which are the monsoon months. In April, the Indian Meteorological Department predicted a monsoon that would be 98% of the long-term average. Normal precipitation is considered to be 96%-104% percent of the long-term average.
India’s agriculture-dependent population has been hoping for adequate rainfall to harvest good quantities of foodgrain and lentils for a second year and bring down inflation, which has led the Reserve Bank of India – the central bank – to raise rates for a 10th time in 15 months. Agriculture accounts for 14% of the economy and a reduced harvest can further lower rural incomes and send food inflation higher than it already is. Inflation in India is the highest among Asia’s major economies.
Bloomberg reported that the wholesale price index in India accelerated 9.06% in May after having increased 8.66% a month earlier, according to official data released on June 14. An index measuring wholesale prices of farm products including milk and lentils rose 8.96% in the week ended June 4 from a year earlier, according to the commerce ministry. India imported record quantities of sugar, lentils and oilseeds in 2009 following the weakest monsoon that year since 1972.
The IMD’s ‘long period’ is 1951-2000 and the department considers probabilities for the country (all-India) and four major regions: north-west India, central India, north-east India and south peninsula. “Over the four broad geographical regions of the country, rainfall for the 2011 Southwest Monsoon Season is likely to be 97% of its LPA over North-West India, 95% of its LPA over North-East India, 95% of its LPA over Central India and 94% of its LPA over South Peninsula, all with a model error of ± 8 %.”
The IMD also employs a six-parameter statistical forecasting system to prepare probability forecasts for five pre-defined rainfall categories. These are deficient (less than 90% of LPA), below normal (90-96% of LPA), normal (96-104% of LPA), above normal (104-110% of LPA) and excess (above 110% of LPA). The forecasted probabilities for the 2011 southwest monsoon season based on this system in percentage for the above 5 categories are 19%, 37%, 37%, 6% and 1%
The department’s ‘Summary of the Update Forecasts for 2011 Southwest Monsoon Rainfall’ has said:
(1) Rainfall over the country as a whole for the 2011 southwest monsoon season (June to September) is most likely to be below normal (90-96% of LPA). Quantitatively, monsoon season rainfall for the country as a whole is likely to be 95% of the long period average with a model error of ±4%. The Long period average rainfall over the country as a whole for the period 1951-2000 is 89 cm.
(2) Rainfall over the country as a whole in the month of July 2011 is likely to be 93% of its LPA and that in the month of August is likely to be 94% of LPA both with a model error of ± 9 %.
(3) Over the four broad geographical regions of the country, rainfall for the 2011 Southwest Monsoon Season is likely to be 97% of its LPA over North-West India, 95% of its LPA over North-East India, 95% of its LPA over Central India and 94% of its LPA over South Peninsula, all with a model error of ± 8 %.
According to Reuters, government officials played down concerns that lower rainfall could fan inflation and dampen growth. “There is no need to press the panic button, as June rains are still above normal,” said Shailesh Nayak, the top civil servant in the ministry of earth sciences which controls the country’s weather office.
While rains could be slightly lower than normal in July, India’s chief forecaster said distribution was key. “There are chances the monsoon will pick up after July 15 once it covers the entire country,” said D. Sivananda Pai, director at the state-run National Climate Center. “Don’t go by the numbers, it is the distribution (of the rains) which we are still hoping to be good.” The weather office predicted 27 centimetres of rain in July compared with long-term average rainfall of 29 centimetres, and rains at 24 centimetres in August, when seeds start maturing, compared with long-term averages of 26 centimetres.
Weather office chief Ajit Tyagi remained optimistic. “Ninety five percent is a good forecast,” Tyagi said. “Had it been 90% of the long-term average then it would have been a cause for concern,” he said, adding that in the past slightly below normal monsoon rains had also seen adequate farm output because they were well distributed in the major crop growing regions.
Explaining climatic conditions over the equatorial Pacific and Indian Oceans, the department’s second long range said moderate to strong La Nina conditions that prevailed in the equatorial Pacific during mid-August 2010 to early February 2011 weakened during subsequent months and dissipated to neutral conditions around mid-May 2011. The latest forecasts from a majority of the dynamical and statistical models indicate strong probability for the present ENSO-neutral conditions to continue during the current monsoon season and the remaining part of 2011.
It is important to note that in addition to El Niño and La Niña events, other factors such as the Indian Ocean Sea surface temperatures (SSTs) have also significant influence on India monsoon. However, the latest forecasts do not suggest development of either a positive or a negative Indian Ocean Dipole event during the 2011 monsoon season. In the absence of strong monsoon forcing from both Pacific and Indian Oceans, intraseasonal variation may become more crucial during this southwest monsoon season and lead to increased uncertainty in the monsoon forecasts.
An afterword about the drought conditions in the USA, centering on the state of Texas, and analysis from the USDA and the World Meteorological Organisation on the extremely dry conditions over northern Europe. This is May 2011 and keeping in mind what happened last year in Russia and Central Asia, we’re going to watch the big crop-growing areas very carefully over the next few weeks.
NASA’s Earth Observatory has said ‘Drought and Heat Create Hazardous Fire Conditions in Texas’ – So far in 2011, more than 1.4 million acres have burned in Texas, a result of some 800 fires. Why is fire activity so extreme in Texas this year? This image reveals high temperatures that contributed to hazardous fire conditions.
Fire needs dry fuel to burn, and weather conditions in March and April turned Texas into a tinderbox. The state began the winter dry season with abundant vegetation, following a moist spring in 2010. But then drought settled over the state in late 2010 and early 2011, culminating in the driest March on record. Many areas received less than 5 percent of their normal rainfall, according to the state climatologist.
In addition to being dry, March and April were warmer than normal. The image shows ground temperatures for April 7 to April 14 compared to long-term average for the week. The red tones indicate that most of Texas was much warmer than average, further drying out the abundant grasses, shrubs, and trees already suffering from a lack of rain.
In its latest World Agricultural Production report (2011 May) the United States Department of Agriculture (USDA), Foreign Agricultural Service has said that the European Union’s (EU) primary wheat and rapeseed region is struggling with dryness. “Dryness prevailed in northern Europe during March and April and continues into May, with far-below-normal precipitation levels and much-above-average temperatures. The high temperatures accelerated plant development so that crops are two to three weeks ahead of normal.”
The report said that dryness is reportedly also interfering with fertilizer uptake by the crops. Both wheat and rapeseed crops need rainfall soon to prevent sharp yield reductions in northern France, northern Germany, England, and western Poland. These affected areas comprise a large portion of the EU’s primary wheat and rapeseed belt.
Planting conditions were generally favorable for EU winter wheat and rapeseed crops last autumn, with adequate soil moisture across most countries, including France and the United Kingdom. In some areas of central Europe however, (including Germany, Hungary, and Romania), rain and wet soils impeded planting, and some fields were likely left unplanted to be sown later with spring crops. Overall, the EU’s winter was rather mild despite one period during late February when minimum temperatures dropped to between minus 15 and minus 20 degrees Celsius for several days in snow-free areas of eastern Germany and western Poland.
The World Meteorological Union, for all its heavyweight authority, has only a couple of paras about the drought conditions in Europe 2011. “A long-lasting dry period persists over large parts of Europe since January 2011. According to data of the Global Precipitation Climatology Centre (GPCC), especially the months February to April 2011 had a considerable rain deficit over large parts of Europe. The 3-month totals over this period ranged between 40 and 80% of the long-term mean 1951-2000 over large areas (see figure below), in many parts of central Europe even below 40%.”
The United Kingdom had extremely dry conditions in March and April, said the WMO, especially in its southeastern parts and experienced its driest March since 1953. The other parts of western and central Europe all had a dry February, March and April. 2011 was up to now one of the driest 10 years in nearly whole Switzerland since 1864. April 2011 was one of the 10 driest April months in Germany since 1881, in continuation of similarly dry April months in 2007, 2009 and 2010. Also the preceding winter 2010/11 was very dry at least in western Europe, causing a very low soil moisture during March and April.