In short, yes, global warming is real. Read the current state of concerns, then a quick recap on the damage done to the ozone layer, and insights into the interplay of greenhouse gases, ice and the ocean.
Ice and Future Livelihood
Alight, this is probably how earth is going to look like (video below), if sea levels rise by an approximate 65 meters (216 feet); this is destined to happen if global warming continues, accelerated by our carbon output. Research already shows that the melting of the ice at the West Antarctic Ice Sheet is in fact unstoppable (Rignot et al., 2014). This is apparently due to ocean water currents, especially the warm water circulation of ocean water beneath the ice, which keeps melting the ice that sits on bedrock that is below sea level (Rignot et al., 2014); and the warm water is believed to be penetrating these areas as an effect of the drastic climate change (Thompson, 2014). Especially the West Antarctic Ice Sheet, although considerably smaller than the East Antarctic Ice Sheet, is vulnerable because of this fact, and the complete dissolution may already result in a 3 meter increase in sea levels (Thompson, 2014) putting cities like Amsterdam, New York or Venice in immense jeopardy. Currently it is about 130 cubic kilometers of ice every year (ESA, 2013) and we will probably be feeling its effects already in the next 200 to 1000 years to come (Joughin et al., 2014); we are talking about our grandchildren and generations to come who will have to deal with the mess we have created. This is serious. We are not even going to talk about the conditions of when the East Antarctic Ice Sheet melts, as it contains 4/5 of all ice on this planet resulting in an unbelievable 65 meters increase (NatGeoSociety, 2013). I am merely going to mention altered deep sea currents, stronger hurricanes, new deserts, mass species extinction, unbearable heat and social upheaval if not even partial anarchy.
Although I am confident that in the decades to come we will find measures to slow down the warming more effectively and will probably be prepared for elevating sea-levels without it claiming millions, no – an approximated billion human lives living in coastal areas, we still have to act now, as individuals as well as together as humans who love their home planet. The efforts of Jason-3, the latest in a series of U.S.-European satellite missions that shall provide us with more insight on top of 23 years of data that already exists on global sea levels, will be helpful to understand how much we are affecting global climate change (Rasmussen, 2015). But why is this so important? Following is why.
A Short Overview on Global Warming
The idea behind the notion of global warming is that our planet is increasingly heating up, and as a result it derives climate change. It roughly started with the human need to industrialise and develop beyond its own understanding. Whether or not China is the largest polluter now, Canada and the U.S. have the highest emissions per capita, or it was all initiated by the European industrial era that started in the 18th, took its toll mid-19th century (World Resources Institute, 2011), is irrelevant for our approach.
Despite the changes in atmospheric temperatures throughout the past 100’000 years, we are in an ‘interglacial’ period when CO2-levels are elevated (ESRL-NOAA, 2013), it is evident that current warming is not solely due to natural causes, but instead it seems humans are driving most of warming (NRC, 2010).
Lets look how we started to make things worse for us by using refrigerators and spray cans.
Ozone Depletion and Hole
Normally, our ozone layer, residing at the lower end of the stratosphere, would protect our troposphere (i.e. the crust-nearest part of the atmosphere/0-10km above sea level) and the biosphere (i.e. the surface where we live) from too much ‘intense’ radiation and the resulting heat being stored. Unfortunately for us, and quite ironically actually, back in the late 1920s, 2 chaps in order to prevent more fatalities from the use of refrigerants, were about to change the course of history: they came up with the ‘miracle’ compound Chlorofluorocarbon (CFCs) as a safe alternative. CFCs were then used as propellants in spray cans, in refrigeration units, solvents and other cleaning agents (Welch, 2014). Massive amounts of CFC and other ozone-depleting gases – like halons, did bring about the largest hole within our atmosphere. Here is what happened:
1) In the stratosphere, the ozone layer that consists of ozones (O3), usually absorbs much of the ultraviolet (UV) radiation coming from radiation. These ozones are actually born from the interplay of Oxygen (O2) and UV.
2) The increased use of chemicals like CFCs and other ozone-depleting gases led for these gaseous compounds to enter the stratosphere.
3) CFCs exposed to UV, had the effect of chlorine (and in other cases bromine) broken apart from the compound. The now freely moving around chlorine/Cl1 strips away an oxygen atom from ozone/O3 reducing the ozone to an oxygen molecule/O2. The new compound Cl1O1 is then approached by an oxygen atom/O1 and it strips away the oxygen/O1 leaving behind an individual Cl1 and an oxygen molecule/O2. The chlorine is now free to destroy more ozone once again.
4) One single compound of CFC/one chlorine atom can destroy 100’000 ozone molecules (EPA, 2010).
It was only after 50 years, in the 1970s when CFC was declared a serious environmental threat, around the same time when the ozone depletion hypothesis was put forward . With holes in the layer, it does not only support an increase in heat that is let in and is trapped in our atmosphere, but these rays in form of radiation (i.e. UV, IR and other types of radiation, which are invisible to us) are dangerous to the living beings dwelling the surface of our planet causing cancer, cataracts, and damage to genetic material, if directly hit (ESRL-NOAA, 2014). And to top it all off, guess where the largest ozone layer hole is! Yes, exactly above the Antarctic, so the melting of the ice can begin. In 1984 the hole was barely there, and now it is as big as the Arctic itself and just above it; no, it’s not a coincidence.
Although most (i.e. 98%) of “the consumption of all ozone-depleting substances has now been phased out” since action has been taken from the mid-1980s (UNEP Ozone Secretariat, 2012, p. xi), the ozone hole over the Arctic, the CFC-alternatives and greenhouse gases are still here.
Watch video about the ozone hole over the arctic.
It seems, that the hole is not the end of our world. But we did this, and our planet has o recuperate. And by recuperation, I mean the planet seeks way to balance out the imbalance we have created. Hasn’t she always done that? So now that we know how we caused long-term damage to the ozone layer, lets look specifically at what the melting brings and how it is promoted by GHG. Only because her ways doesn’t mean we have to push her, right?
The Greenhouse Effect and Ocean Conveyor Belt
When Earth gets energy in form of heat from the sun, it manages to balance how much should stay and be stored, and how much ought to be released back into the atmosphere; or at least this was the case until we, humans embarked on our own, separate mission. Larger reflective surfaces like the ice caps, glaciers or clouds throw back around 30% of the energy into the atmosphere (Riebeek, 2010). But with the constant melting even this capacity is being compromised. And in the end, everything that is not reflected is ‘stored’, usually by oceans, land and the atmosphere and is known as the “natural greenhouse effect” that keeps our planet at comfortable temperatures (Riebeek, 2010; EPA, 2014). As the rocks and sand, seas and air warm, and eventually release heat, a considerable amount never makes it into the vastness of the atmosphere. This is because of greenhouse gases (GHGs) that bind and trap the energy. GHGs are “gaseous compounds in the atmosphere that are capable of absorbing IR, thereby trapping and holding heat in the atmosphere” (Lallanilla, 2015). About 90% of all human-produced heat trapped by greenhouse gases are additionally absorbed by the oceans, as they are vast and have high heat storing capacity (Levitus et al, 2012). Thus, what is leading to the unusual warming of our planet are the human-amassed long-lived GHGs in our atmosphere that either trap the reflected or the stored-and-released heat. These GHG molecules keep the heat alive like “tiny heaters” do (Riebeek, 2010). Melting ice flowing into the oceans and warming oceans are not to be taken lightly. This affects the thermohaline circulation tremendously. From thermo (heat) and haline (salt), two factors that influence density, these massive deep underwater currents move constantly from north to south and back again in a particular pattern around the globe (UCAR, 2011; NatGeoEdu, 2015). They move around the water, and turn it over in the entire ocean, upside down; this is “somewhat like a giant conveyor belt, moving warm surface waters downward and forcing cold, nutrient-rich waters upward” (NatGeoEdu, 2015). We have less nutrients from deep water being mixed into warmer surface due to lack of CO2 in deep waters that algae use for their photosynthetic processes, the first link in a very vast food chain and biological carbon circulation. These algae are consumed by plankton, further up the food chain, some animals would release the CO2 back into the atmosphere. The proliferation of these algae though is higher than the consumption of algae by the zooplankton, leaving the algae, after having used all the nutrients, to die and sink to the bottom of the sea with CO2 bound to their cells (Lighthouse Foundation, 2013). This directly affects ocean nutrient distribution, all marine life, land fauna that depends on fishes, and global climate. Just to emphasise the sizes we are tapping into, a current e.g. the Antarctic Circumpolar Current is so large, that it moves more water than all rivers of our planet combined, and now take into account the faster melting Antarctic sea ice making sea water less denser, and you may draw the picture yourself.
Now, how does it all fit together? For once we have the capacity of oceans to hold CO2 reduced, as the oceans warm up; we have cold ice waters messing with deep water formation in polar waters as it is released on the surface from the melting; so oceans are heating up because of various factors like melting of ice, and greenhouse gases being absorbed threading the ecosystem of currents, living beings and climate.
It seems we contributed so much GHGs into our atmosphere that it is affecting the climate in our entire biosphere. The most controversial of these GHGs we have been adding so enthusiastically into our atmosphere are carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). Compared to the pre-industrial period, the CO2 concentrations are 40% higher at current state (EPA, 2014), and at an all-time high compared to the past 800’000 years (NRC, 2010). Methane levels are at a soaring 250% since the pre-industrial era, and N2O at 118% (Solomon, 2007). While methane is 21 times more efficient at absorbing heat rather than CO2, methane only lasts 10 years in the atmosphere compared to centuries CO2 can last (Lallanilla, 2015). In the past few decades, they have already made their effects clear in increasing water and air temperatures around the globe. It is however burning of fossil fuels and change in lands such as deforestation that have caused the most disruptions (EPA, 2014).
Here are some extended measures recommended by the EPA or by the NRDC that can be undertaken to prevent higher production of GHGs. More about the imbalance of Energy coming into our atmosphere and leaving it can be read on EPA’s Climate Change page.
To wrap things up…
If are you driving a car that uses fuel, always buy the latest gimmicks and gadgets, leave the heating on at home all day long to keep your room warm and cozy, buy non-biodegradable products that requires them to be burned or some other source of energy to put it away, or even eat meat, you are most probably supporting, and by supporting I mean disregarding, global warming and climate change, or at the least giving it a low priority. Remember, it is increased demand that will cause greater supply. Hence, with every new product you buy, or service your hire, think whether you are guilty of adding to what is already a mess.
The next blog post talks about what we can do to fight it in the new era of technology.
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