The 20th Conference of the Parties (COP 20) to the United Nations Framework Convention on Climate Change (UNFCC) held last week in lima, set the stage for the final year of negotiations towards a new global climate agreement to be signed by all countries, including India, next year in Paris. Therefore, climatologists and scientists tell SHAlINI SAKSENA, it is time India wakes up to the climate change reality, moreso with delayed winters in the Capital where the maximum temperature shot up alarmingly to 29 degrees C as late as December 1 this year
Delhiites are finally feeling the chill. However, this December has been the warmest as compared to many years. The mercury touching 29°C in the Capital on December 1, 2014 and it being declared the hottest day since 1901, came as a shocker for the layman but environmentalists and climatologists were not surprised. For, all along they have been saying that hot days are on the increase and winters on the decline. This is not the first time that Delhi has recorded such a high temperature in December.
On three other occasions — on December 9, 2000, December 9, 1994 and December 12, 1968 — the Capital recorded temperatures hovering around 29°C. The highest it went was 29.5°C on December 5, 2011.While the climate in Delhi during the winters varies between 5°C to 25°C, experts say that one should get used to the variations and that this kind of December heat is a direct result of global warming.
“The present weather conditions in the Capital can be the result of global warming together with other factors like variations in land use and industrialisation. This includes deforestation, pollution and several other factors. Global warming is a phenomenon one can’t ignore. It will continue and the oscillations in climate will become even more common,” climatologist Murari lal says. “In the past few years, temperatures in certain parts of northern India have dipped below minus. And in summers, one sees the mercury soaring to 48°C. One also sees floods and droughts. These extreme weather conditions are all part of climate change per se,” lal explains.
Hence, there’s snowfall in New York and Europe so early in the month of November and a recorded temperature of 30°C in November in Delhi. Due to the Arctic polar vortex and sudden stratospheric warming events, temperatures within the stratosphere warm dramatically over a short time impacting the southern parts of the Earth. “The possibility that a hot December in Delhi is linked to a weak El Nino also can’t be ruled out,” lal says.
The National Weather Service’s Climate Prediction Centre had recently predicted that the odds for formation of El Nino stood at 80 per cent. However, it now says that it appears that this winter, it will be down to 58 per cent. If El Nino does form, forecasters say it will be a ‘weak’ one. Scientists are still trying to find the reason for this shift.
One possibility is that it has been extremely warm in the Pacific Ocean. This has made it difficult for the El Nino to develop. Another reason could be the variations in land use and local weather changes. But Dr D Raghunandan, president of the All India People’s Science Network, has a slightly different take on this and tells you that to say with surety that the reason why it is so hot in Delhi is variation in land use and deforestation will be difficult. “It is not as if Delhi-NCR has witnessed massive deforestation. Random cutting of a few trees doesn’t affect the climate. Also to say that global warming is the only contributor would be wrong unless more research has been done,” Raghunandan explains.
He is, however, quick to point out that the trend shows winters are decreasing and summers increasing due to global warming. “The reduction in winters and its intensity and hotter summers mean that climate is changing and temperatures rising not just in India but globally too,” he said at a panel discussion on climate change talks organised by Indian Women’s Press Corps recently.
Climatologists do agree that to nail a pattern in short winters needs more research.The problem, experts feel, is that the impact of climate change is seen over a long period of time. For most people it is a matter of a rise of only 2°C — instead of the temperature hovering at 45°C it will now be 47°C. But scientists know the huge impact of this increase. There is peak in demand for electricity which means more coal is burnt to generate it which, in turn, means that we are adding to the carbon budget. last year, India’s carbon emissions shot up to 7.7 per cent. While this figure may not be as high as in other countries, India can no longer ignore the fact that it is the third largest polluting country in the world, after China and the US.
“When one talks about climate change, various factors have to be considered. No single major cause can be linked to global warming. It is an amalgamation of a number of reasons which impact the overall climate. So while for some nations, in the northern parts, a warmer world may bring good news, for island nations, Africa and countries in the tropical belt it spells disaster,” lal points out.
The fifth assessment report of the Intergovernmental Panel on Climate Change, 2013, said: “Global warming continues despite a slow-down in surface temperature rise over 1998-2012. Global mean surface temperatures increased by 0.89ºC between 1901 and 2012. Each of the last three decades has been warmer than any preceding decade since 1850. Almost the entire globe (including India) warmed between 1901 and 2012. It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century.”
The report also said, many areas on the globe have observed more hot extremes than cold extremes. Wet extremes over most mid-latitudes land masses and wet tropics will become more intense and more frequent.“In India also, many studies have shown an increase in heatwaves and decrease in coldwaves. Studies show an increasing trend in maximum temperatures and decreasing minimum temperatures. And, this trend is here to stay. As such we should expect less coldwaves during winters,” Dr DS Pai, head scientist, lRF division, National Climate Centre in Pune, says. He adds that it is possible that the intensity of cold will be less or just the number of winter days will reduce.
Observed temperature changes in the Capital may be in tune with expected changes in temperatures due to global warming, but the below average rainfall during monsoons can’t be attributed to global warming. “Though increasing trend in the extreme rainfall has been observed over central India, no trend has been observed in seasonal average rainfall. This is the case with most parts of India,” Pai says.
Climate change, one is told, happens over a period of time. And therefore, a steady rise in temperature or for that matter winters setting in late or its intensity reducing may not register but India can no longer ignore that it is witnessing a change and it is time that some strong measures are taken urgently. “We can’t do without burning coal but we also have to take into account that it adds to the carbon emissions and that there will come a time when there will be no coal. So we have to look for alternative sources of energy. Why not now and maybe we can at least minimise the temperature rise before touches a 6-8°C rise,” lal asserts. A study by 19 established scientists from five continents, predicts that “on the basis of mid-range climate warming scenarios, for 2050, 15 to 37 per cent of species in our sample will be committed to extinction.”
“Keeping in mind the present scenario of manmade activities that threaten the environment, by 2100 AD, the level of pollution would be between 900 and 1,100 part per millennium in volume as against just 280 in the 1940s. Already, human activities have harmed the ecosystem so much that it will take a few hundred years for it to restore itself. In order to maintain any kind of balance in the environment, pollution level must be kept within 450 part per millennium by volume,” lal insists. However, the examination and analyses of climate change in South Asia have to be understood against the physical, economical and societal environments of many nations located in this region. The socio-economic environment of several countries in this region is characterised by high population density and relatively low economic growth. Many countries are vulnerable to extreme climate events like cyclones and floods.
One is told that since the climate is not static, any assumption made about the future based on the past may be inappropriate. Assumptions about the probability, frequency and severity of extreme events should be re-evaluated. Climate change issue has presented decision-makers with a set of formidable complications: A considerable number of uncertainties have the potential for irreversible damage to our ecosystem.Therefore, meteorologists insist that people understand the difference between climate change and global warming. While the terms are often interchanged, they are very distinct from each other.
Global warming, though, is a more specific term. It refers to increases in Earth’s average temperature because of greenhouse gas build-up in the atmosphere. Global warming causes climate change which is a broader term. It refers to changes (increase or decrease) in long-term weather patterns like temperature, rainfall or snowfall. A warmer Earth, from global warming, will lead to changes in rainfall patterns, a rise in sea level and a wide range of impacts on plants, wildlife and humans. When scientists talk about the issue of climate change, their concern is about global warming caused by human activities.
The India Meteorological Department (IMD) predicts that from here on, the chill will return to not just Delhi but certain parts of north-west and central India from this week onwards. “The reason why it has been relatively hot this year is because there has been less rainfall and this means that there is less moisture in the air. Also, if one notices, there are hardly any clouds. The weather is clear even at 8 am. There is no obstruction for the sun’s rays raising the day temperature. The sky is clear and this is heating the atmosphere leading to a high in the day temperature,” IMD director BP Yadav says.
The western disturbance may not be directly linked to a hot December, but it has been weak this year. Western disturbance is a term used in India, Pakistan, Bangladesh and Nepal to describe an extra-tropical storm originating in the Mediterranean which brings sudden winter rain and snow to the northwestern parts of the subcontinent.
“Since it has not been as strong, its impact is being felt now. With the prediction of fog, rainfall and snowfall in upper regions of the country, Delhi will feel the cold. This is something that usually occurs around mid-December and continues till January,” Yadav says. So those who have not yet taken out their woolens because early December was virtually sizzling, this weekend may the right time to take out sweaters and jackets before the chill catches up and the winter finally sets in.