Final warning

The influence of human activities on the climate is clear and growing. If left unchecked, global warming will have an irreversible impact on people and ecosystems, says the UN's Intergovernmental Panel on Climate Change (IPCC) in its latest synthesis report. It calls for near-zero emissions of greenhouse gases by the end of the century

Last Updated: Thursday 17 September 2015






Climate change is real
The evidence
  1. Each of the last three decades has been successively warmer. 1983-2012 was the warmest 30-year period in 1,400 years in Northern Hemisphere
  2. Surface ocean (upper 75 metres) warmed by 0.11°C per decade between 1971 and 2010
  3. Since the beginning of industrial era, CO2 emissions have led to ocean acidification. The pH of its surface water has decreased by 0.1; acidity increased by 26%
  4. Greenland and Antarctic ice sheets lost mass at a higher rate between 2002 and 2011. Northern Hemisphere spring snow cover decreased in extent; glaciers shrunk worldwide
  5. Between 1979 and 2012, Arctic sea-ice extent decreased by 3.5-4.1% per decade; Antarctic sea-ice extent increased by 1.2-1.8% per decade. Antarctica witnessed strong regional differences, with sea-ice increasing in some regions and decreasing in others
  6. Mean sea level rose by 0.19 metre between 1901 and 2010. It is the highest rise in the last two millennia
  7. Limiting warming to less than 2°C relative to 1861- 1880 requires containing emissions to 2,900 Gt of CO2. Nearly 1,900 Gt of CO2 was emitted by 2011
The projection
  1. Surface temperature is projected to rise in the 21st century under all possible scenarios. Heat waves will occur more often and last longer. Extreme rainfall events will become more intense and frequent in many regions. The ocean will continue to warm and acidify, and global mean sea level will continue to rise
  2. Such changes will obviously lead towards hotter climate. There will be more frequent hot and fewer cold temperature extremes on daily and seasonal time-scales as global mean surface temperature increases. Heat waves will occur with a higher frequency and longer duration. Occasional cold winter extremes will also continue to occur

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  • IPCC synthesis Report [AR 5]

    IPCC synthesis Report [AR 5] released on 1/11/2014: Myths & Realities

    Dr. S. Jeevananda Reddy
    Formerly Chief Technical Advisor ÔÇô WMO/UN & Expert ÔÇô FAO/UN
    Fellow, Andhra Pradesh Akademy of Sciences
    Convenor, Forum for a Sustainable Environment
    Hyderabad, India
    Tel. (040)23550480;

    The following are few headlines taken from the IPCCÔÇÖs Summary Synthesis Report:

    1. Observed changes and their causes: Human influence on the climate system is clear, and recent anthropogenic emissions of greenhouse gases are the highest in history. Recent climate changes have had widespread impacts on human and natural system.

    1.1 Observed changes in the climate system: Warming of the climate system is unequivocal, and since 1950s, many of the observed changes are unprecedented over decades to millennia. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, and sea level has risen.

    1.2 Causes of climate change: Anthropogenic greenhouse gas emissions have increased since the pre-industrial era, driven largely by economic and population growth, and are now higher than ever. This has led to atmospheric concentrations of carbon dioxide, methane and nitrous oxide that are unprecedented in at least the last 800,000 years. Their effects, together with those of other anthropogenic drivers, have been detected throughout the climate system and are extremely likely to have been the dominant cause of the observed warming since the mid-20th century.

    1.3 Impacts of climate change: In recent decades, changes in climate have caused impacts on natural and human systems on all continents and across the oceans. Impacts are due to observed climate change, irrespective of its cause, indicating the sensitivity of natural and human systems to changing climate.

    Evidence of observed climate - change impacts is strongest and most comprehensive for natural systems. In many regions, changing precipitation or melting snow and ice are altering hydrological systems, affecting water resources in terms of quantity and quality (medium confidence). Many terrestrial, freshwater, and marine species have shifted their geographic ranges, seasonal activities, migration patterns, abundances, and species interactions in response to ongoing climate change (high confidence). Some impacts on human systems have also been attributed to climate change, with a major or minor contribution of climate change distinguishable from other influences. Assessment of many studies covering a wide range of regions and crops shows that negative impacts of climate change on crop yields have been more common than positive impacts (high confidence). Some impacts of ocean acidification on marine organisms have been attributed to human influence (medium confidence).

    1.4 Extreme events: Changes in many extreme weather and climate events have been observed since 1950. Some of these changes have been linked to human influences, including a decrease in cold temperature extremes, and an increase in warm temperature extremes, an increase in extreme high sea levels and an increase in the number of heavy precipitation events in a number of regions.

    My Observations

    IPCC switched from prediction to projection. The report observed ÔÇ£recent anthropogenic emissions of greenhouse gases are the highest in historyÔÇØ but in global temperature there is a hiatus, plateau, pause or whatever you want to call it for the last 17 years. And yet without taking this in to account IPCC says ÔÇ£warming of climate system is unequivocalÔÇØ. IPCC now brought in new word ÔÇ£Climate SystemÔÇØ. They did not dealt, what they mean by climate system. Whether this includes natural inbuilt variations along with the ecological changes; regional general circulation patterns; and extra-terrestrial impacts, etc or it refers to only global warming?

    From the above it is clear that IPCC was choosy in using the words ÔÇô most of them are ambiguous like human influence. Nowhere, they referred the word ÔÇ£global warmingÔÇØ. Also, it is not clear whether the word ÔÇ£climate changeÔÇØ is referred as de-facto global warming. They were very tactful this time. They did not use the word around half the global temperature raise as global warming and instead used qualitative words like ÔÇ£dominantÔÇØ. The other qualitative word is ÔÇ£recentÔÇØ.
    In 1.4 IPCC states ÔÇ£number of regionsÔÇØ, which means the impact is not uniform to globe. The impact is observed at some zones only. By reading the two sentences under ÔÇ£1 - Observed changes and their causesÔÇØ one wonders what IPCC wants to tell the world. Here IPCC uses ÔÇ£widespreadÔÇØ. These have no meaning except to confuse and interpret as it suits their ideology. Generally we use this word in weather forecasting referring to a particular region.
    The measurements of greenhouse gases started in around 1956 then where from the word ÔÇ£in historyÔÇØ come. When we use a truncated part of rhythmic series ÔÇ£recentÔÇØ give false alarm lead to misleading conclusions based on the part of rhythmic variation the selected data represents.
    Most of the projections are highly hypothetical and not based on facts. IPCC states ÔÇ£it is based on the author teamsÔÇÖ evaluations of underlying scientific understanding and is expressed as a qualitative level of confidence (from very low to very high) and, when possible, probabilistically with a quantified likelihood (from exceptionally to virtually certain), where appropriate, findings are also formulated as statements of fact without using uncertainty qualifiers.ÔÇØ That means they used different qualifiers as per convenience. In science, it should be of uniform in nature.
    The following are some of my observations on the implications of climate change specifically for India.
    Effects of Climate Change on Weather:
    The largest chunk of the IPCC synthesis report focuses on the changes in weather patterns and projections related to extreme weather events. It pronounces that these changes are expected to have cascading effects on the health of the economy as well that of the people.
    The report observed that the number of monsoon break days is expected to increase while the number of monsoon depressions will see a decline; and at the same time it observed that ÔÇ£mean and extreme precipitation during the Indian summer monsoon is expected to increaseÔÇØ. This cannot be true as with the decrease of depressions rainfall & extreme rainfall decreases as the Indian monsoon precipitation is primarily linked to low pressure systems.
    Indian monsoon systems are related to general circulation patterns in different seasons coupled with natural rhythm in meteorological parameters. This we can see from the thumb rules. One such thumb rule is: when low pressure system is located in the Kolkata [Calcutta] region then Hyderabad region will be dry [no precipitation] in southwest monsoon season. This is true even today. Also the onset of monsoon over Kerala Coast follows the pattern of 52 year cycle. The All India southwest monsoon precipitation follows the 60-year cycle. With this, from 2017 to 2046 the precipitation will be below the average part of 60-year cycle. In this period expected more drought years and less flood years and thus frequency of occurrence of floods in NW Indian rivers will be few; and consequently the temperature will be higher and thus evaporation. This will affect the dry-land agriculture in many years.
    Extreme weather events: cyclones, floods and droughts
    The IPCC report observed that the frequency of cyclones likely decrease in 2030s. Floods and droughts are likely to increase in India since there will be a decline in seasonal precipitation, coupled with extreme precipitation during monsoon.
    Cyclonic activity
    During 1891 to 1990 cyclonic disturbances in Arabian Sea are 259 [143 depressions, 47 cyclonic storms & 68 severe cyclonic storms] and in Bay of Bengal they are 1212 [767 depressions, 260 cyclonic storms & 185 severe cyclonic storms]. Majority of cyclonic storms and severe cyclonic storms are seen in pre-monsoon and post monsoon seasons. In the pre-monsoon season the temperature reaches to maximum peak and during post-monsoon season the temperature comes under declining phase to reach minimum in a sinusoidal curve. The data presented by Joint Typhoon Warning Centre on clones per year during 1945 to 2000 showed a 56 year cycle. This follows the northeast monsoon precipitation pattern of Andhra Pradesh State in India. During 1945 to 1972 the frequency was above the average and from 1973 to 2000 the frequency was below the average. From 2001 to 2056 will repeat 1945 to 2001 pattern. That means 2029 to 1956 follow the frequency of below the average. The average no. of cyclones per year are 10; during the below the average part they are 2 to 8 and during the above the average part are 10 to 16 [except in two years with 4 & 8].
    In 1977 severe cyclone around 10,000 people died, in 1990 cyclone only around 1000 people died; though the later one is more severe than the 1977 cyclone. The death toll was higher in 1977 as the area is low lying ÔÇô below sea level. In the 2014 severe cyclone the loss of human life was around 3 to 5 persons but latter addition was around 50. So the impact relates to terrain conditions, seawall protection [natural mangroves, etc], destruction of the coast line due to illegal developmental activities and disaster management actions. The cyclonic tracks covered the entire east coast line of Andhra Pradesh, with more frequent around Srikakulam, East Godavari, Krishna, and Nellore districts. Though it was made possible to bring down human losses with better disaster management, the same was not achieved in animal, crop, property losses. This is part of natural rhythm and nothing to do with global warming. Let me present the precipitation variations in three meteorological sub-divisions:
    Met Sub-division parameter SWM NEM
    Coastal Andhra Mean*, mm 507 (52) 375 (39)
    C.V., % 22.2 38.8
    Lowest 309 088
    Highest 780 703
    Rayalaseema Mean, mm 422 (60) 204 (29)
    C.V., % 28.8 41.9
    Lowest 192 012
    Highest 791 455
    Telangana Mean, mm 722 (80) 107 (12)
    C.V., % 23.5 60.3
    Lowest 371 002
    Highest 1186 310

    * the values in brackets are % of annual mean; SWM = southwest monsoon;
    NEM = northeast monsoon; C. V. = coefficient of variation -- Estimates
    based on 1871 to 1994 data published by IITM, Pune, India

    Period part of cycle 28-year average precipitation, mm
    CA R T CA R T
    1889-16 Above average 509 432 743 330 188 091
    1917-44 Below average 477 386 673 410 205 104
    1945-72 Above average 532 423 761 356 198 108

    CA = Coastal Andhra, R = Rayalaseema, T = Telangana
    28 year averages represent below the average and above the average
    periods of 56 year cycle ÔÇô the cycles of SWM and NEM follow opposite patterns
    IPCC report states that the IndiaÔÇÖs temperature will increase from 1.7 to 2.2 oC over 1970 level in 2030. But, the global average temperature has not shown any increase for the last 17 years [1998 to 2014] ÔÇô in this report IPCC used term like in 2030 instead by 2030!!!
    The actual data shows the raise in minimum temperature is higher than that in maximum temperature and yet the value of 2011 is less than 1970 in the case of minimum temperature; the same in the case of maximum temperature shows a small raise from 1970 to 2011. After correcting to 60-year cycle component the trend is very little. The global temperature 60-year cycle varied between -0.3 to +0.3 oC. In such a scenario, can we expect that much rise in Indian temperature?
    The temperature is highly variable from season to season; year to year; soil to soil; coast to inland to hilly terrain; etc. The temperature follows the opposite pattern with floods and droughts. Also, crop development is influenced not only by temperature but also by the soil moisture, relative humidity, soil temperature, soil fertility, plant density, fertilizer use efficiency, etc.
    The raise in minimum temperature is more in association with the urban heat-island effect. Also, the met network is more concentrated in urban areas. Thus it is over emphasized in the averaging of temperature. The met network is sparsely distributed in rural areas and thus it is underemphasized in the averaging of temperature. The net result results in less than the observed average temperature. The crops are mainly located in rural areas and thus the temperatures in these zones are below the average.
    Cold waves and heat waves
    In the case of India the heat and cold waves are associated with western disturbances from northwestern region. Their movement to south and east are related to general circulation patterns in the south and east. The extreme temperatures [maximum or minimum] have not exceeded the extremes presented in the 1931-60 normal book [IMD ÔÇô Red Book]. Temperature presents opposite pattern to precipitation pattern. That is during wet period the temperature comes down over the average and during the dry period the temperature goes up over the average. The cyclic part of the temperature is part of observed temperature. When local terrain, forests are destroyed we get changes in meteorological parameters including temperature.
    Effects of climate change on Agriculture:
    The IPCC report observed that ÔÇ£Climate change will especially affect the livelihoods of people, agriculture the mainstay of the Indian economy, will see dramatic changes in yields, affecting peopleÔÇÖs right to food security.
    The two natural resources that are vital for agriculture are the soil and the climate. Man has no control as yet on the climate and needs to adapt to it. The farmer is aware that crop production is limited by climate. He also knows that some crops do well in his region whereas others do not. In tropical regions like India, the production is limited by moisture while in extra-tropical regions it is limited by energy. When a model developed under extra-tropical conditions [SORGF of Texas A & M] tried to apply to semi-arid tropical conditions and found it fails, with poor correlation coefficients both in terms of production of biomass and grain yields. This is even after modifying several sub-models relating to energy factor. When the moisture sub-model was replaced with moisture model developed for the tropical semi-arid conditions the correlation coefficient gone up from 0.35 & 0.37 to 0.85 & 0.81 for biomass and grain yield. Crop development is related to several factors like temperature, photo-period, relative humidity, soil moisture, soil fertility, crop population, etc. Each crop and variety has a range of temperature, where its development needs are met. As a result temperature is not an important factor in India. The main factors for crop production are precipitation/irrigation and fertilizer. Under irrigated agriculture, yield is a function of several factors including soil type, fertilizer, water [quality & quantity], water logging/salinity factors, etc.
    Pollution-induced changes in air and water quality, as well as changes in weather pattern, are expected to have wide-reaching effects on the health of Indians, according to the IPCC report.
    To avoid the criticism on the impact of global warming on health, they mixed this with pollution. In fact we are fighting the IPCC and UN on this issue for the long. DonÔÇÖt mix the pollution with global warming when we are talking of health hazards on life farms. It is entirely different issue and not related to global warming.
    Concluding Remarks
    The presentations in Synthesis Report of AR5 are quite different from the previous two reports of AR5. This report is filled with ambiguous statements. To avoid the confusion particularly in relation to the impact aspects instead of using the generalized word climate change, use the specific part of climate change, namely global warming, ecological changes, natural variability, etc. This gives the clarity to public on the issue of global warming.
    Separate the global warming component from ecological change component. Tell the public, is global warming component since 1951 to date is 0.1 oC or between 0.1 and 0.2 oC? Then only we get the real picture on what will be the global warming by 2100! At present lump sum is used as global warming. The ecological changes part impacts at local and regional scales and not at global scale. As the surface data present an over estimate of ecological change component, use the satellite data for the purpose of separating global warming component from ecological change component.
    In the case of sea level change, separate the impact due to global warming from natural variation, land sinking from oil, gas & water extraction, destruction of coast line ÔÇô particularly protective walls of nature, etc components.
    In the case of changes in ice, separate the impact of global warming from the impacts of natural disasters such as earthquakes, volcanoes, nuclear tests, and sporting, etc components.
    There is no impact of global warming on Indian weather systems, water resources availability and agriculture production. This is even up to 2100. Natural variability impacts are depicted as caused by global warming only. Extreme weather events are part of natural variability.
    IPCC at last recognized the importance of pollution in health. It is also an important factor even for agriculture production.
    IPCC must not use ambiguous terminology and present where the data is quantitatively validated.
    Dr. S. Jeevanda Reddy

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