Geology is mainly the study of non-human-induced changes taking place throughout earth’s history. Geologists think of the last 50 million years as the recent past, both because they represent only about one percent of the age of the earth and because plate tectonics, the geologic process that controls conditions within the solid part of the earth, has operated without significant change during that time. This is the exact period to gain an insight into the earth’s climate that can be applied to the present-day global warming debate.
Scientia Pakistan reaches out to the renowned geoscientist, Prof. Dr. Nayyar Alam Zaigham, for its exclusive ‘Natural Disaster Edition’ to gain an insight into the historical study of earth’s climate cycles and how much they impacted earth’s geographical features and its environment. We take a look at the primary reasons for the growing number of natural disasters on every part of the earth due to these climate changes.
Below are excerpts of Dr. Zaigham’s brief conversation with our editor-in-chief Saadeqa Khan.
Saadeqa: Geology is mainly the study of non-human-induced changes taking place throughout earth’s history. How could it better contribute to study climate changes?
Dr. Zaigham: It has been observed that the climate system is continually changing due to the extremely complex interactions among the various components of the Earth System as well as the external energy sources. In fact, the Earth spins around its inclined axis and simultaneously rotates around the sun. Top of it, it is further diagnosed by NASA that the sun with its whole solar system (inclusive of Earth) orbits around the center of the Milky Way Galaxy at an average velocity of 828,000 km/hr or 230 km/sec. Thus, it is deduced that the global climate variability will remain the consistent and complex phenomena controlled by these three, maybe more, movements as well as constantly varying impacts of the sun and other various celestial bodies as encountering on the orbital-way at the unknown varying periods of the very long-term orbital-journey around Milky Way Galaxy.
However, on the basis of the overall research assessment of our earth as a member of the present ‘Solar System’, it was identified that the ‘Earth System’ itself inherent four various complex functioning components or the mega “Spheres” (Figure-1), like:
- the Lithosphere (i.e., solid earth) that includes all types of the exposed geological and geomorphological features and the whole inside of the earth;
- the Atmosphere (i.e., the gaseous envelope surrounding the Earth) that extends about 560 km from the surface of the earth and comprises four different sub-spheres (i.e., troposphere, stratosphere, mesosphere, and thermosphere);
- the Biosphere (all the concerning living organisms) that includes all living things, like the trees, the birds, the flies, the viruses, the animals and even the people who are the most notorious creature pocking their nose in all four the earth’s ‘spheres’; and
- the Hydrosphere, that contains all the liquid, solid and gaseous water-types as rivers, lakes, snow, glaciers, icebergs, huge icecaps, ice caps, ice sheets, and ice shelves, permafrost, and seasonally frozen grounds, gulfs, seas, and oceans of earth inclusive of atmosphere & biosphere too.
Interactively, all the spheres are dependent on each other, as indicated by the numbers and the arrows under the strict control of solar energy and its other cosmic radiations as well as from the other celestial bodies of the universe. Some of the nutshell deductions indicated some of the salient interactive effects, with reference to arrow and numbers plotted on the model, are described as follow:
1: the atmospheric chemistry and temperature effect the organisms on the biosphere;
2: the atmospheric chemistry and temperature effect the weathering of rocks on the lithosphere;
3: the atmospheric chemistry and temperature effect the evaporation of the hydrosphere;
4: the photosynthesis on the biosphere affects the concentration of the atmospheric CO2;
5: the plants aid weathering (physical and chemical) of rocks of the lithosphere;
6: the plants control water transfer from soil to atmosphere from the hydrosphere;
7: the weathering and erosion control nutrient supply to the life on land and in oceans;
8: the volcanic eruptions add CO2and aerosols to atmosphere;
9: the locations of continents control circulation pattern of oceans of the hydrosphere;
10: the rainfall and runoff erode the land surface;
11: the soil water limits the plants growth in biosphere;
12: the ocean circulation controls how much CO2 is removed from the atmosphere; and on and so forth.
These interconnected ‘spheres’ of the Earth System play the greatest and the most intriguing roles in describing many great things that make this planet habitable in terms of a) how the natural processes and cycles of the Earth work, and b) how human activities are effecting and changing them.
Practically, it was identified from the above discussion that all the four earth components and the external energy sources play key roles in a clear understanding of the creation of climate zones over our planet and its variability trends with respect to the passage of time periods. Thus, the earth has a variety of climatic zones right from the north-pole to the south-pole. These climatic zones have variable climatic variability trends within themselves individually too on micro, macro, and/or mega levels.
The climate of any area/region depends on the micro, macro, or regional impacts of various natural and/or anthropogenic factors, i.e., the distance from the sea, the ocean currents, the elevations (land relief or topography), latitude, atmospheric behavior (direction of prevailing winds and/or the el-Nina phenomena), distance from the equator, earth tectonic processes, celestial cosmic activities, axis inclination & rotation of the earth and other anthropogenic urban, industrial, global political interest, etc. The different combinations of these factors collectively affect the climate in short and/or long terms showing the varying climatic changes in regions accordingly.
[Note: Brief is taken and described with reference to Book entitled “Hydro-Tectonics & Fault-Zone Aquifers in Desert Terrains of Saudi Arabian Crystalline Shield”, written by Nayyer A. Zaigham & Omar S. Aburizaiza, ISBN# 9960-06-943-5, Published in 2019 by Scientific Publishing Center, King Abdulaziz University, Jeddah, Saudi Arabia]
Saadeqa: What do you think are the main reasons for earth’s climate fluctuation between cold and warm periods? How much earth’s tilt fluctuation relative to its orbital plane contributed to these changes?
Dr. Zaigham: Our knowledge about the earth’s natural system is limited, and still, we cannot claim that we have explored everything as discussed during your first question. In the past, scientific knowledge was almost blind-fated, and people were reluctant to accept new things that oppose their old traditional rigid beliefs. Today, we know that earth is moving around Sun, but in 1543, when Nicolas Copernicus detailed his radical theory of the Universe that the earth, along with the other planets, rotates around the Sun, he had to face widespread hate and outrage of some orthodox leaders over his theory.
Today we know that earth is not only revolving around Sun but also around its own axis as well as around Milky Way Galaxy. Such triple movements of Earth and the solar energy & cosmic radiations/currents from known and unknown celestial bodies may be creating a bit complicated climate & its variability trend(s). We are experiencing global climate changes and altered weather (especially the temperature and the rainfall/solid precipitation patterns in every part of the world due to new weather cycles that the earth has faced before during past geological historical periods. No doubt, the anthropogenic activities affect the Earth’s weather as well as the climate significantly, but varying region to region and human activity to activity.
The climate change effects are evident everywhere. The satellite images have helped to identify the climate changes in comparison with the past. For examples, current images show on-set of the drought in several parts of Europe and the Siberian regions.
NASA Image, released on June 26, 2020, revealed that the 2019-20 winter in Europe was the warmest on record, with little snow (Figure-2). The spring was also drier and warmer than normal, with a historic heatwave in the middle of May. Ultimately, it resulted in the long-term rainfall deficits, persisting heat waves, and increased evaporation, which have depleted some of the groundwater supply beneath central and eastern Europe.
Even, eastern Siberia is famous for some of the coldest wintertime temperatures in the Northern Hemisphere, but in 2020, it has also been the region’s wildly high temperatures and wildfires as reflected by NASA Image released on June 26, 2020.
Similarly, the NASA image of March 25, 2020, shows the depleting growth trends of the Arctic sea ice as compared to long-term average levels due to regional winter warm for most of the middle latitudes of the Northern Hemisphere. Nowadays, Antarctica is also being investigating for the increase of the earth’s temperature as the glaciers are melting faster than last few decades ago.
Likewise, in the 1970s and 80s, certain injurious chemicals were found to be accumulating in Earth’s stratosphere, where sunlight breaks them into components that destroy ozone. The ozone layer naturally absorbs ultraviolet radiation from the Sun, so less ozone in the stratosphere means greater risks for sunburn, skin cancer, and cataracts. The primary reason behind the increasing of severe drought periods and damage to the Ozone layer, particularly over the European & Arctic ice sea regions, is considered due to the massive industrial revolutions. However, NASA released a report on February 13, 2018, which described that the Earth’s ozone layer is slowly healing, and we now have proof that policy decisions have helped.
In the case of Pakistan, an article in ‘Nature-LETTERS/2006’ published led by Kerstin Treydte of the Swiss Federal Research Institute that identified two types of heavy oxygen trapped in the trees in northern areas. Based on the extracted cores of the trees, the yearly tree’s growth rings were assessed to estimate the ratio of normal to heavy oxygen. The end results of the study revealed that the yearly snowfall is stretching back more than 1,000-years in comparison to the local snowfall records. The phenomenon was further linked in an accompanying article in ‘Nature’ by Michael Evans of the Arizona, Tuscan, USA, who pointed out that the biggest increases in snowfall occurred in the last 150 years approximately coincident with the industrial revolution & greenhouse gas increases.
But in this connection, I gave my views in an interview-2006 to a local correspondent of SciDevNet, Aleem Ahmed, that was published on April 27, 2006. I told him that the increase in the snowfalls, as another explanation, could be the direct impact of the very huge flood-irrigation options by using the largest canal systems, barrages, dams, special linked-canal networks for the large-scale forming in the northern areas initially developed in the 1830s. It was pointed out that such that intensive irrigation practices coincide with the western ‘industrial revolution’. For more than 60-years or so, we have built, even are still building, a number of dams in the northern part of the country to retain the water there for more agriculture without adequately considering the southern part of the country. Consequently, the significant increase in the precipitations and decrease in the temperatures in the northern parts and decrease in precipitation and increase in the temperatures in the southern parts of the country were prevailing for a long time – causing the climatic discrimination by the unforeseen anthropogenic activities.
I have been working on it for several years, and my research concluded that the increasing earth’s temperature is not new; but even around 18 thousand years ago, the earth had experienced another climate cycle that completely altered its natural oldest system on the semi-global scale. We are working to figure out that what are the primary reasons behind these climate effects still.
Saadeqa: Do you agree that climate variations are mainly due to processes (man-made) occurring on earth, as contrasted to the Sun?
Dr. Zaigham: As I mentioned above, the atmosphere above the earth has different layers mainly responsible for the earth’s natural weather patterns. Humankind activities affected them directly due to which many parts of the world are experiencing little to no rainfall as compared to the past. Cyclones, tornados, and torrential rains are causing floods and massive destruction in the coastal regions.
Presently, Pakistan is also experiencing less rainfall, particularly Baluchistan (area-wise the largest province) and Sindh Province. Its economy is primarily dependent on agriculture, and thus, the low precipitation is gradually draining it out. Around 100 years ago while the discharge of Indus flow was about 150 cusecs within the delta region, there was an excellent irrigation model in & around the Indus Delta. But now, in the same areas, down to Kotri barrage, the water flow is usually much below the decided ‘limit of 10 cusecs of flow’ except the over-flooding time of Indus River. Moreover, many parts of Pakistan are experiencing much less than 100-millimeter rainfall (averaging to 50-mm) due to the onset of the climate changes due to the irrational divergence of the Indus River System to the northern parts of Indo-Pakistan in the form of huge canal networks, barrages, dams, and other much accusive water utilization option. That is why most of the northern areas of Pakistan have better climates as compared to the lower Sindh down to delta coastal region as well as the nearby areas of Baluchistan too.
The Tharparkar district, the part of the Greater Thar Desert, of Sindh province, once famous for its green-established large sand dunes, but now turned into a ‘lost desert ecosystem due to the man-made intensive interventional huge activities. We have started open-pit coal mining ventures in Thar, constructed the coal-fired power plants, and other linked urban & industrial development too. Considering the examples of such huge older urban & industrial developments in Europe, as discussed above, we will face or maybe, the verse repercussions. However, it has been assessed that these development projects will alter the total Thar’s ecosystem in terms of the annual rainfall, fauna & flora, grazing landscapes, agriculture lands, groundwater aquifers encountering from near-surface shallow down to different depth levels, even the deep-basement ones and etc. Moreover, it is also assessed that such enormous physical mining development activities may invoke strong seismicity directly within the Tharparkar region. Now, the Government, beneficiary companies, and NGOs are working to make the artificial ecosystem in Thar for irrigation and livelihood. In fact, the thing we are worst to visualize because once we, the humans, destroy a natural ecosystem, it could never be refixed.
Similarly, in our rural and mountainous regions of Pakistan, we blindly cut the forests that caused massive floods, glacier melting, and other severe climate changes accordingly. We need to learn that the earth’s natural system has its own ability to restraint. Likewise, the vivid coastal urban & industrial developments along the more than 1000-km long Pakistan coasts by reclamations of sea-lands likely appear to badly affect the coastal climate and other coastal-marine ecosystems too. The living example is the vast DHA urbanization in Karachi, as the people are now experiencing the side effects.
In fact, urban development, including land-use changes, dense building developments, localized heat emissions, various human activities, etc., has a great impact on the local climate of a city. One of the best-known effects of urbanization is the urban heat island effect, which develops when urban cooling rates are slower than rural ones. Some of the main factors that may bring about the difference in temperatures between urban and rural areas, like as i: the high heat capacity of the buildings in the urban area compared to surrounding rural areas, resulting in more of the sun’s energy being absorbed and stored in urban; ii: the high-density buildings in urban areas block the view of the sky and reduce the heat release back to space; iii: the man-made heat emissions by buildings, air conditioning, transportation and industries in urban areas; and iv: the dense development in urban areas, which reduces wind speeds and inhibits causing suffocation. Ultimately, the urbanization effects collectively result in increasing the ‘greenhouse gas impacts’ causing randomness in annual precipitation. Karachi city is one of the best examples.
Saadeqa: Why do we need to implement a strict building code in Pakistan?
Dr. Zaigham: I have illustrated the situation with a minor example of the big residential built during about last decades, the 1970s-2021, along the Clifton coastal belt of Karachi, which shows that good fieldwork is essential while planning those megaprojects. Many of our planners don’t have sufficient knowledge of the risk assessment. In most cases, it is the main point of the disaster management policy worldwide. Having said that, several countries of the world including Pakistan are facing the worst disaster management. Like in Dubai, they have built shopping malls, hotels, resorts, and massive projects without giving importance to the environmental research against the business/financial plans or considering the side effects of the amazing mega-constructions within one of the worst desert ecosystems, which owe the Arabian/Persian Gulf, a very shallow marine body. Now, the climatic & other earth-related seismo-threats are gradually creeping up on the micro-macro levels. I have presented my research studies on Karachi-Clifton issues on 24th October 2007 at Urban Resource Center, Karachi and on the deterioration of the Arabian/Persian Gulf issue in 2012 at Riyadh, Saudi Arabia.
Whether it is Karachi, Dubai, or any other big city of the world, a strict building code with proper fieldwork and risk assessment strategy is essential for the mega constructions. We can use modern computer technology for making a digital model before commencing construction work. I have worked on the groundwater system in Saudi Arabia, adjacent to these areas and still developing different climate models considering the present ongoing trends in comparison to historic to prehistoric ones – the amazing realities appear.
Moreover, in the case of Karachi, a book was written entitled “Seismic Zoning of Karachi & Recommendations for Seismic Design of Buildings in 2000 by A. Razzak Loya, Nayyer Alam Zaigham, Mushtaq A Dawood, and published jointly by the Association of Consulting Engineers, Pakistan (ACEP) and Karachi Building Control Authority (KBCA), which was taken as the approve ‘Building Codes’ for Karachi city. It is interesting to point out that in the recommendation section, it was advised to update the book-findings after five years by incorporation the precise mapping data of the land-fill areas of the mega Karachi city. So far, nobody has come forward from ACEP and/or KBCA, though the copies of the book are now out of stock and are not available for new engineers. One can imagine – how serious we are about safety issues!
Saadeqa: What is the status of geological research in Pakistan? Do our educational institutions provide modern tools and research facilities like remote sensing to the students and researchers?
Dr. Zaigham: You can figure out the status of geological research in Pakistan on your own with the statement that the geological survey of Pakistan is functional without a Director-General for more than two years. The universities are neither being providing modern research facilities and/or adequate research funds to the deserving students willing to undertake research projects on much-needed topics related to threats related to the seismotectonic and climatic change issues in the region.
Moreover, researchers and teachers are getting salaries that are insufficient to meet their basic necessities, so how could the researchers work peacefully when are trapped by the financial crisis.
It is a lacuna within under developing countries that when a senior professor got retired from a university, they toss him out like a spare part of society. The fact is different. In developed countries, the research persons of the universities are immediately taken as Emeritus Professors after having retired. I myself was appointed after retirement as Outstanding Research Professor, with full financial benefits & working facilities and high honor, by King Abdulaziz University, Jeddah, Saudi Arabia. Still, I am linked with them and working on one or the other research issue.
However, the Higher Education Commission (HEC) of Pakistan can fully recharge its system with such experienced individuals to boost a research culture in Pakistan, especially in the education-cum-professional research sectors.