Before Too late

Cause of Global Warming

This is not new news. These changes started 18,000 years ago, as the earth emerged from the Pleistocene Ice Age-- a time when ice-covered mammoths and mastodons roamed the earth. Global warming is occurring at a faster rate and with greater intensity than scientists predicted even a few years ago. As the increase in the average temperature of the earth’s near-surface air and oceans in recent decades and its projected continuation. It is caused when more solar energy is trapped in the Earth’s atmosphere than can escape into space. Carbon dioxide and methane are the two compounds causing the problem. A high quantity of those compounds is coming from power plants and transportation. Levels of all key greenhouse gases (with the possible exception of water vapor) are rising.

Concentrations of carbon dioxide (mainly from burning coal, oil, and natural gas), methane and nitrous oxide (due to agriculture and changes in land use), and CFCs (produced by industries) are increased at an unprecedented rate resulting in a higher absorption of heat and leading to "enhanced greenhouse effect". This could lead to greater warming and increase in temperature, which in turn, could have an impact on world's climate leading to the phenomenon known as "climate change".

How Global Warming Works:

Global warming has become a major problem. It is caused when more solar energy is trapped in the Earth’s atmosphere than can escape into space. Carbon dioxide and methane are the two compounds causing the problem. A high quantity of those compounds is coming from power plants and transportation. The rise of temperatures threatens many dangerous consequences, such as drought, disease, floods, lost ecosystems, sweltering heat, and rising seas. Temperatures have increased by about one degree Fahrenheit over the last century and should rise another three to nine degrees by the end of this century. Heat waves, droughts, and wildfires will occur more often and with much more intensity. Disease carrying mosquitoes will expand their range and species will become extinct.

Climate Change

Climate change is any long-term significant change in the “average weather” that a given region experiences. Average weather may include average temperature, precipitation and wind patterns.

Reducing the rate of global climate change induced by growing levels of greenhouse gases in the atmosphere is recognized as the world's greatest environmental challenge.

Evidences Of Climate Change

Rising Temperature and increased warming:

The most dramatic change has been in the temperature, with measurement records suggesting that warming by 0.3-0.6 °C has already taken place since the 1860s. Eleven of the last twelve years rank among the warmest years in global surface temperature since 1850. The rate of warming averaged over the last 50 years is nearly twice that for the last 100 years.

Carbon build up in the atmosphere:

Carbon dioxide is the dominant contributor to current climate change due to fossil fuel burning. The rest is due to land-use change, especially deforestation, and, to a lesser extent, cement production. (Source:IPCC, 2001) It is estimated that the atmospheric concentration of Carbon dioxide has increased from a pre-industrial value of 278 parts-per million (ppm) to 379 in 2005.

Glaciers are melting:

Mountain glaciers and snow cover have declined, on average, in both hemispheres, and have contributed to sea level rise by 0.77 millimeters a year from 2 1993 to 2003. Further, shrinkage of the ice sheets of Greenland and Antarctica have contributed to a sea level rise of 0.4 millimeters a year between 1993 and 2003. Further, snow cover is decreasing in most regions, particularly in spring. The maximum extent of frozen ground in the winter/spring season has decreased by about 7 per cent in the Northern Hemisphere since 1900.

Arctic is warming:

Average Arctic temperatures increased at almost twice the global average rate in the past 100 years. Satellite data since 1978 shows that the average Arctic sea ice extent has shrunk by 2.7 per cent per decade.

More water, but not everywhere:

More precipitation has been observed in the eastern parts of the globe whereas southern side has experienced more drying and intense droughts.

Fig: 1 A Schematic View of the Components of the Global Climate System, their Processes and Interactions and some aspects that may change.

Can Biotechnology Help to Slow Global Warming?

As a biotechnologist, new researches should be focused and channelized to reduce the emission of green house gases. One such research is being carried out to construct gas emitter converters that employ the use of GMO to convert harmful gases in to not so harmful gases.

Scientists are building cleaner cars and are modernizing power plants, but another solution is being studied: biotechnology. Can genetically engineering plants play a role in slowing down global warming? Some think so. A genetically modified organism is one that carries and/or inherits an artificially introduced modification in its genome.

Some people don’t believe that biotechnology would be able to help to slow down global warming enough to warrant development of biotech crops. They believe that the concentration should be on the power plants and the transportation industry. Even if the genetic technology gets off the ground, it will be unlikely that there will be any visible benefits for 20 to 50 years and we don’t have that kind of time.

Plant Biotechnology:

In recent research, scientists have discovered a mutant enzyme that could enable plants to use and convert carbon dioxide more quickly, effectively removing more greenhouse gases from the atmosphere.

In a recently completed research, American scientists have discovered a more efficient variant of the key enzyme involved in CO2 sequestration by plants during photosynthesis, the ribulose 1,5- bisphosphate carboxylase/oxygenase (RuBisCO). The main aim of the study was to direct the evolution of RuBisCO variants with improved kinetic and biophysical properties that could enable plants to use and convert CO2 more efficiently.

Previous scientific attempts of engineering more efficient RuBisCO enzymes were primarily focused on mutating specific amino acids within RuBisCO and then seeing if the change affected CO2 conversion. In this study, the researchers used a different approach which consisted in inserting randomly mutating RuBisCO genes into bacteria (in this case Escherichia coli) and screening for the most efficient resulting RuBisCO enzymes.

In nature, E. coli bacteria do not carry the RuBisCO enzyme and they do not effectuate photosynthesis nor do they contribute to the carbon sequestration from the atmosphere. The researchers thus isolated genes encoding RuBisCO and a helper enzyme from photosynthetic bacteria and added them to E. coli. Such genetically modified E. coli were able to fix and convert CO2 into consumable energy when the other nutrients were withhold and the bacteria relied on RuBisCO and carbon dioxide to survive under these stringent conditions.

Subsequently the RuBisCO gene was randomly mutated, and these mutant genes were inserted to E. coli. The fastest growing strains carried mutated RuBisCO genes that produced a larger quantity of the enzyme, leading to faster assimilation of carbon dioxide gas. The RuBisCO variants that evolved during three rounds of such random mutagenesis and selection were over-expressed, and exhibited 5- fold improvement in specific activity relative to the wild-type enzyme.

The herbicide-tolerant (HT) crops allow minimize tilling to practically zero. They save both - humus and fuel. Transgenic cultivars of rice are developed to avoid flooding of fields reducing the methane production.

Crop varieties with improved efficiency of nitrogen utilization were developed by genetic modification and are prepared in laboratories. Such varieties reduce the fraction of nitrogen released as N2O.

Trees genetically modified for faster growth are likely to use up water even faster than the fast-growing trees currently used in industrial plantations.

Swedish researcher engineered aspen with a gene from an oats which controls the response of plants to day length. The resulting tree was able to grow in winter day lengths as well as summer.

Industrial Biotechnology:

It is one of the most promising new approaches to pollution prevention, resource conservation, and cost reduction. It is often referred to as the third wave in biotechnology.

Biocatalysts have been developed to unlock the hydrogen and carbon stored in carbohydrate molecules of plants and transforms them into bioethanol. Bioethanol delivers significant climate change benefits. Because it is derived from renewable resources, bioethanol can be used to recycle carbon dioxide emissions in a closed loop from atmosphere to plant to ethanol back again.

Bioethanol reduces the need to use fossil fuels in processing: one study estimates that to drive one mile on E85 bioethanol derived from corn Stover will require only 14% of the energy inputs compared to the same distance driven using traditional gasoline derived from petroleum.

Effects of Global Warming on Humanity

The effects of global warming are difficult to quantify because of the complicated relationships between air temperature, precipitation quantity and pattern, vegetative cover and soil moisture. However, it is likely to harm humanity in following ways:

Over the next hundred years, the earth's surface temperature is projected to increase by 1.4 to 5.8 °C. As a result, large quantities of water locked in the polar ice caps and glaciers will be released as a consequence of warming. This, together with an increase in the thermal expansion of the oceans, will make the global mean sea level rise by 9 cm to 88 cm.

A rise in sea level could inundate and erode coastal areas, increase flooding and salt-water intrusion; this will affect coastal agriculture, fisheries and aquaculture, freshwater resources, human settlements and tourism.

Further, higher summer temperatures will increase the demand for energy for space cooling. The frequency and duration of heat waves is due expected to increase, which, combined with greater humidity and urban air pollution, will cause a greater number of heat related illness and deaths.

The availability of water in the rivers of India, Australia, Southern Africa, South America, Europe and the Middle East is expected to decrease. Salt-water intrusion from rising sea levels will further reduce the quality and quantity of freshwater supplies.

By the 2080's, substantial dieback of tropical forests and grasslands is predicted to occur, particularly in parts of South America and Africa. Environmental damage such as overgrazed rangeland, deforested mountainsides, and denuded agricultural soils means that nature will be more vulnerable than previously to changes in climate.

Indian Perspective

India has a 7500-km long densely-populated and low-lying coastline, and an economy that is closely tied to its natural resource base. Hence, it is considerably vulnerable to the impacts of climate change. Change in climate could mean:

Additional pressure on ecological and socio-economic systems that are already under stress due to rapid urbanization, industrialization, and economic development. Extreme precipitation events and the possibility of more frequent flash floods in part of India and drought in others. An increase in rainfall is simulated over the eastern region of India but the northwestern deserts may see a small decrease in the absolute amount of rainfall.

Increases in temperature and seasonal variability in precipitation are expected to result in more rapid recession of Himalayan glaciers. In fact, the Gangotri glacier is already retreating at a rate of 18-20 meters a year.

Warmer and wetter conditions would increase the potential for a higher incidence of heat-related and infectious diseases. The incidence and extent of vector-borne diseases, which are significant causes of mortality and morbidity in tropical Asia, are likely to spread into new regions on the margins of present endemic areas as a result of climate change.

Reduction in agricultural productivity especially in areas growing wheat (which is a temperature dependent crop) is expected. Further,yeild of rice could also decrease due to change in rainfall pattern.