Primer on Climate change, Global warming and other related matters

The wildfire burning in California, USA, heat waves in Delhi, India, diminishing biodiversity in Upper Guinea and land loss due to sea levels rise in the Caribbean.

Climate change and global warming are no longer esoteric concepts. Their effects have immediacy in our daily lives. We constantly check the weather reports.  Build on highlands. A country moved its entire capital to avoid the consequences of climate change. The insurance industry coopts climate models and reports in assessing premiums.  You have to be under the proverbial rock to not have come across one climate-related issue or weather reports of flooding or drought. Whatever reports you have read relating to climate change; brace yourself more will be coming. We are not making as many changes as required to stem the ugly way nature is been treated. Many still treat climate crises as something that can wait. A secondary inconvenience. The business of humans first.

The truth is as humans have moved at a breakneck pace in exploiting earth resources, we are birthing imbalances in the ecosystem, some of it which we already see, such as; increased susceptibility to wildfires, droughts, sea levels rise, ecological disturbances, weather unpredictability, and others. Headlines, like those in the opening paragraph, have become commonplace in our news cycles. Earth our home planet is undergoing profound negative changes with a lot of it directly linked to human activity.  The UN Paris accord on Climate change advises that we need to keep global warming to below 2 degrees Celsius pre-industrial age.

 How did we get here and what can be done?

Our economic system, rapid growth, and remarkable march on civilization have put a strain on the planet. Human-induced global warming. Yes, while Earth has its historical episodes of cooling and heating. This is unprecedented. The consensus within the scientific community firmly puts the problem this time at the footstep of homo sapiens. The only specie capable of impacting earth systems to such degree. And rather ironically the group most impacted by the negative changes. We caused the problem and we can also fix it. How did we get here? To understand we must start at the beginning, a throwback to when humans first began to redirect weather and climatic conditions that were hardwired into nature’s feedback systems.

 The Industrial Revolution 

The start of one of the most important journeys in human history began with the utilization of coal as an energy source. Centuries before the start of the Industrial Age, the Chinese and Romans had made a discovery; the dark carbonaceous deposits underneath the earth's crust could be burnt and used for heating. The story changed rapidly around the 1700s. In England. Here, at the beginning of the industrial age coal’s utility will be widely exploited, acting as the energy backbone to British innovation and from there the rest of the world. While this must have seemed such a positive development, we now know there’s a penalty to be paid. Coal together with its chemical siblings, crude oil, and natural gas emits carbon dioxide, particulate matter, and methane as fuel by-product.

This negative externality of fossil fuel was the underside of the industrial age’s growth leading to the proliferation of a stew of pollutions that continues to this time. The steamboat, cotton gin, and locomotive trains are today's marine transport, mass factories, and superhighways. Nothing much has changed between then and now except better information to understand the consequences of dirty fuel. The great leap of the 18th century and today's global economy were anchored on dirty fuel. 

the cost of the revolution

As the Industrial age intensified the use of fossil fuel to provide cheap energy, kickstart their industries, and improve the society they invariably started the process, we have over time continued and made worse.  Coal like the other dirty fuels is a good servant but a bad master. Therefore, the world's energy sources must be diversified; cleaner alternative energy sources brought to the table. The adoption of these new energy sources can reverse the legacy of the past. The ways of the past have brought a burden. 

The dirty fuel which drives modern civilization has a flaw at its core. They produce an effect that exacerbates global warming. As the revolution soared so did this hidden externality pari passu. 

Understanding how the temperature of the earth works

The Aztecs worshipped the sun as did the ancient Egyptians. 

The sun exerts a cardinal role on our home planet as its biggest object by providing the energy for photosynthetic plants, controlling the planetary motions, and sustaining the earth's surface temperature through heat and light.  This last part is important to understanding climate change and global warming. Here is how the sun’s energy packaged as radiation in conjunction with the atmosphere keep the earth inhabitable. We know that convection, conduction, and radiation are the three ways in which heat is transferred from one body to another. The sun via radiation mode of heat transfer sends down light and heat to the earth by virtue of being the hottest object in our solar system.

The story doesn't end there however. A second mechanism involves the interplay of the earth's surface, the atmosphere, and specific gases swirling in the atmosphere.

The atmosphere and the Greenhouses gases (GHG)
The short wave energy from the sun has three components; reflection, absorbtion and transmission. For the purpose of earth climate, the transmitted energy can be considered solely for now. Suffice to say, about 50% of the initial energy from the sun transmits to earth.

The earth surface emits the radiation received; no longer in the short wavelength but as long-wave infra-red back into the atmosphere where gas molecules with three or more atoms called greenhouse gases trap it and produce a warming effect. This is what is known as the greenhouse effect. The common greenhouse gases are water vapor and carbon dioxide. Others are CFC, methane, and HFC. This greenhouse gases trapping outgoing radiation is what has got scientists and policy makers alarmed. We have put out more and more of the gasses since the age of the industrial revolution. 

Are Global warming and Climate change one and the same?

The short answer is NO.

Global warming is the rise in the average ground and air temperature across the globe. When you take the mean of the temperature across the latitudes and longitudes, it is clear temperatures have increased upwardly since the 1970s. Global warming is a symptom of a disease, a warning sign something is wrong.

Climate change on the other hand deals with far more components of weather than just temperature. Other parts of weather such as rainfall, arctic ice, sea level rise and the shift in all these variables from set markers quantified using statistical methods is what makes up climate change. Its important to note the change can be caused by natural variations or human actions such as burning of fossil fuels. 

Keeling Curve

           

  Understanding the carbon dioxide output is crucial to our reversal of global warming. As a greenhouse gas, it has the longest residence time in the atmosphere. Charles David Keeling with his work starting in 1958 charted the first continuous CO2 levels in the atmosphere. The rise and rise of CO2 shown famously in the Keeling curve (above) created unprecedented warming in recent times culminating with 2016 being the hottest year since standardized record-keeping began.

Since the industrial age, we have been putting out more greenhouses gases chiefly carbon dioxide. These have come from power plants, factories, agriculture, and transportation sectors. We can't control the sun's activity (too far and so hot)but we can reduce the effects of global warming by tamping down on activities that spew carbon. 

Other important concepts to help us

Climate forcings are factors natural or man-made that alters the sun-earth energy budget leading to either warming or cooling of the earth. Positive forcing leads to warming while negative forcing infers cooling is taking place.  The Milankovitch cycles, volcanic eruptions, and solar cycles are some of the natural climatic drivers; anthropogenic forcing include the burning of fossil fuel and deforestation.

Carbon sink and source

Any material that captures carbon is a sink while any that produces it is a source. A sink and a source are interrelated as any sink could be a source tomorrow. Coal was once considered a carbon sink saved in the lithosphere. There's active research ongoing to develop artificial carbon sinks but no major scaled up breakthrough has been achieved.  

The oceans, marshes, mangroves, and forests are some carbon sinks.

Consequences of climate change

• Flooding
• the spread of diseases and mutation of vector
• Drought
• Poor agricultural yield and soil degradation etc

Africa's risk to Climate change and Global warming

Africa needs to be on a war footing as it reacts to climate issues. The continent already suffers excruciating poverty, low infrastructural development and lies at the bottom of the human development index. Little wonder it ranks as the most vulnerable to the threats posed by global warming (IPCC reports). There is a paradox - Africa contributes the least amount of greenhouse gases but its ecosystem and population will experience some of the worst effects of is climate stress. African leaders must drive their economy propelled by clean energy, plan with an integrated approach when tackling urbanization, population stress, waste disposal management and invest in the education and health of its citizens. They need to set their priorities right.

    As individuals and small communities, we can play roles that decrease the climate problem - practice water conservation at home, plant trees, use energy efficient appliances, advocate for green policies, reuse kitchen waste in compost, recycle plastics and educate others about climate issues. 

  further reading;
  
 1. https://www.acs.org/content/acs/en/climatescience/climatesciencenarratives/what-is-the-greenhouse-effect.html
  

 2.  https://climate.nasa.gov/scientific-consensus/