In this part in addition to new subjects, I have highlighted some of responses from previous sections for further discussion. Please leave you comments to support/weaken any of the following statements:
1) @Harry ten Brink recapitulated a summary of a proof that CO2 is such an important Greenhouse component/gas. Here is a summary of this argument:
"a) Satellites' instruments measure the radiation coming up from the Earth and Atmosphere.
b) The emission of CO2 at the maximum of the terrestrial radiation at 15 micrometer.
b1. The low amount of this radiation emitted upwards: means that "back-radiation" towards the Earth is high.
b2. Else said the emission is from a high altitude in the atmosphere and with more CO2 the emission is from an even higher altitude where it is cooler. That means that the emission upwards is less. This is called in meteorology a "forcing", because it implies that less radiation /energy is emitted back into space compared to the energy coming in from the sun.
The atmosphere warms so the energy out becomes equals the solar radiation coming in. Summary of the Greenhouse Effect."
At first glance, this reasoning seems plausible. Nevertheless, it is based on these assumptions that the contribution of CO2 is not negligible and any other gas like N2O and Ozone has minor effect. The structure of this argument is supported by an article by Schmidt et al., 2010:
https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2010JD014287
By using the Goddard Institute for Space Studies (GISS) ModelE radiation module, the authors claim that "water vapor is the dominant contributor (∼50% of the effect), followed by clouds (∼25%) and then CO2 with ∼20%. All other absorbers play only minor roles. In a doubled CO2 scenario, this allocation is essentially unchanged, even though the magnitude of the total greenhouse effect is significantly larger than the initial radiative forcing, underscoring the importance of feedbacks from water vapour and clouds to climate sensitivity."
The following notions probably will shed light on the aforementioned argument for better understanding the premises:
Q1) Is there any observational data to support the overall upward/downward IR radiation because of CO2?
Q2) How can we separate practically the contribution of water vapor from anthropogenic CO2?
Q3) What are the deficiencies of the (GISS) ModelE radiation module, if any?
Q4) Some facts, causes, data, etc relevant to this argument, which presented by NASA, strongly support this argument (see: https://climate.nasa.gov/evidence/)
Q5) Stebbins et al, (1994) showed that there exists "A STRONG INFRARED RADIATION FROM MOLECULAR NITROGEN IN THE NIGHT SKY" (thanks to @Brendan Godwin for mentioning about this paper). As more than 78% of the dry air contains nitrogen, so the contribution of this element is not negligible.
2) The mean global temperature is not a good diagnostic to study the sensitivity to global forcing. Because given a change in this mean value, it is almost impossible to attribute it to global forcing. Zonal and meridional distribution of heat flux and temperature are not uniform on the earth, so the mean temperature value is misleading.
3) "The IPCC model outputs show that the equilibrium response of mean temperature to a doubling of CO2 is about 3C while for the other observational approaches this value is less than 1C." (R. Lindzen)
4) What is the role of the thermohaline circulation (THC) in global warming (or the other way around)? It is known that during Heinrich events and Dansgaard‐Oeschger (DO) millennial oscillations, the climate was subject to a number of rapid cooling and warming with a rate much more than what we see in recent decades. In the literature, these events were most probably associated with north-south shifts in convection location of the THC. The formation speed of North Atlantic Deep Water (NADW) affects northerly advection velocity of the warm subtropical waters that would normally heat/cool the atmosphere of Greenland and western Europe.
I really appreciate all the researchers who have participated in these discussions with their useful remarks, particularly Harry ten Brink, Filippo Maria Denaro, Tapan K. Sengupta, Jonathan David Sands, John Joseph Geibel, Aleš Kralj, Brendan Godwin, Ahmed Abdelhameed, Jorge Morales Pedraza, Amarildo de Oliveira Ferraz, Dimitris Poulos, William Sokeland, John M Wheeldon, Joseph Tham, and Boris Winterhalter.
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Link to the discussions of Global Warming (Part 1):
https://www.researchgate.net/post/Global_Warming_Part_1_Causes_and_consequences_of_global_warming_a_natural_phenomenon_a_political_issue_or_a_scientific_debate
Link to the discussions of Global Warming (Part 2):
https://www.researchgate.net/post/Global_Warming_Part_2_A_growing_threat_or_nothing_to_worry_about_An_effect_of_greenhouse_gases_or_a_natural_climate_change
Link to the discussions of Global Warming (Part 3):
https://www.researchgate.net/post/Global_Warming_Part_3_A_growing_threat_or_nothing_to_worry_about_An_effect_of_greenhouse_gases_or_a_natural_climate_change
Global warming is a natural phenomenon, now increses due to political causes and can be rectified by the scientific knowledge.
Global warming is a science and technology discussion. Sustainable monitoring of research and innovation essential to mitigate global warming in climate change processes considering the protection of ecology of environment of planet earth.
Plant trees, cover our planet Earth with greeneries to save it, and fight against the global warming (@ 0.40 degree per year); if you do not keep the Earth covered up, it will cover you in near future
Hi Massoud and members of this thread.
First, Global Change (or Climate Change, or Global Warming?) is:
1) A reality unveiled by many scientific observations and methodologies (@AbjihitMitra).
2) Is not a natural phenomenon (@AnupKumarSrakar). On the contrary it is an anthropologically induced change of the Earth's global climate. The indicators of this change are manyfold. Too much to cite here. But real threats for humanity are among these indicators, e.g., drought, more intense hurricanes and storms and coastal and land inward inundations with thousands drowning. A trend of increasing variability of climate has been observed as well,...leading to hell for farmers. Last but not least there is sea level rise due to melting Ice sheets in Greenland and Antarctica and retrieving glaciers globally. These are not naturally, induced phenomena. THey are human induced, mainly due to a wildly growing world population which increasingly depletes natural resources especially by deforestation. This increasing world population, by its increasing industrialization, traffic, residential heating to name a few, brings more and more GHG's in the atmosphere. On their turn the GHG's induce an increased global atmospheric and oceanic temperature, and these induce anthropogenic induced climate change.
3) Global warming is a science and technology discussion (@AshokKaran). I can confirm that this is not a discussion at all. In the scientific community, more and more corroborated phenomena are described and scenario's published. There is no discussion at all about these climate change discoveries in science. The only ones discussing are politicians, CEO's, and the very rich. And there are also those who don't discuss at all, because they are trying to survive in changing climatic conditions. Ain't that as clear as the diminishing amounts of drinking water?
4) We don't need discussion, we need urgent action like European children and adolescents have made clear in their strikes for immediate action to stabilize our climate again. They fight for a durable future for their generation, because politicians especially, even if they discuss this matter, they take no actions at all.
Cheers
Tropic Cascade. Within the grounds of this concept we have seen that small parts can add up massively to cause a net effect in behaviour and change ecology of an area. A example of such is what occured at yellowstone national park in the 90s in response to river erosion and diversity loss due to herbavores lacking natural predators. Therefore i still won't accept that climate change will ever be one or the other relating to politics of science as a debate.
A natural phenomenon caused by the auto-reaction by our tortured planet suffering from artificiality
P. K. Karmakar
Hopefully besides greeneries and mono-species agriculture there will be some natural biotopes left as well. They have taken care of a stable climate in the past. And we do need biodiversity to safeguard natural stability. On most continents, there are hardly any natural biotopes left as they have been destroyed for mostly opportunistic motives.
Simply said, without natural and biodiverse biotopes, no natural and more stable climate. Simple as that.
Cheers
Frank
Frank V., on your point #2 above.
You say "warming is not a natural phenomenon"
From 1910 to 1940, global temperature increased by ~0.5C, and CO2 increased by ~7 ppm.
From 1970-2000, temperature increased by ~0.6C, and CO2 increaased by ~45 ppm.
If CO2 increase was the cause of 1970-2000 warming, why was it only 20% as efficient as teh CO2 increase over 1910-1940?
To suggest all warming is human-produced displays ignorance of various natural climate drivers (forcing factors) that have operated over many missions of years, and continue to operate.
To M.R. I disagree with your point b1.
IR radiation up to space is lower at 15 microns because those CO2 molecules are located at high cold altitudes where IR emission rates are low (T^4 rule). Thus, IR emission at 15u back to Earth is also low and thus does not increase 15u back radiation, but lowers it. Extra energy obtained by CO2 with 15u absorption is rather transferred via collisions to other molecules (N2, O2, Ar) at those high altitudes.
The simple (but not complete) answer to your Q1 and Q2 is that weather satellites every day take advantage of the fact that quantum IR absorption bands for CO2 and H2O are diagnostic of those molecules. The warming contribution of each is more complicated.
What is missing from this information is the height at which the observation is made and the water vapor content of the gas. Higher up is cooler. How higher up? High enough to exclude water vapor content because of its atomic weight?
Prior to 1940 there were no satellite data and very little upper atmosphere data (via baloons). Temperatue was near-surface.
Water is restricted in altitude because it condenses, not because of its molecular weight. (Temperature decreases with altitudes, called the lapse rate.) CO2 has a much greater molecular weight and rises higher than H2O because it does not condense.
Sustainable energy use for the socio-economic development of human society to minimize green house gases specially carbon-dioxide which contribute about 50% global warming in climate change processes by increasing present forest area from 18% to optimum 30%in agro-forestry system of cultivation to consume carbon-dioxide by photosynthetic green plant to produce carbohydrate and oxygen in the atmosphere may the solution through environmental resource management and impact assessment considering the protection of ecology of environment of planet earth.
Global warming is a phenomenon cause by natural and anthrological energy use discussion as scientific debate come to conclusions as sustainable energy use for the socioeconomic development of living specially human society considering the protection of ecology of environment of planet earth.
A.K.
Agree that the environment is important in controlling CO2. About half of past human CO2 has entered the oceans and plants/soil, and substantial increased plant photosynthesis is well documented.
Today, activity surrounding the term global warming is political not scientific. For a number of reasons internet searches yield a ratio of 10 or 20 fake science sites to one scientific one. You have to read them all. I suggest several thoughts based on what I have read.
Studies of CO2 concentrations based on the content of glaciers claim that during the time, 600 million years ago, when earth had it's biggest explosion of life specie types, CO2 concentration was 16 times what it is today. Earth was very lush in greenery. It is likely that the dinasour could not thrive in our atmosphere today because of our low CO2 concentration.
CO2 concentration is known to vary significantly in cycles of thousands of years.
Mankind, of course, does affect CO2 concentration as does the fruit fly and the rats in Baltimore. I am reminded of the classic joke about the flea crawing up the elephant's leg with sex on it's mind!
I urge you to keep an open mind and stick to science where most of us here live.
To those of you who still believe in catestrophic death of the planet by mankind, why are you not concentrating on reducing the population explosion, a much more serious threat?
In socio-economic development of human society to mitigate global warming and climate change processes government policy and political issues may interpret the situation. Climate change are natural processes and it should be monitored through environmental resources management and impact assessment with scientific debate and discussion.
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