Is it a reality or myth? Climate change is a natural process. It depends upon the solar radiation received by the Earth and other atmospheric phenomena. Recently, there is a discussion at the global level that the climate change phenomenon is mostly due to increase in anthropogenic global warming (AGW). So, how much is the impact of AGW on the climate change and what are the other factors responsible?
Please
Could you first read other very similar questions asked in this topic here at ResearchGate before you ask yours?
And as a first answer I refer you to the most recent United Nations report on climate Change
The so-called IPCC 5th assessment report for free on the web:
https://www.ipcc.ch/report/ar5/wg1/
Vishambar. Did you ever saw the CO2 profile for past 800,000 year. It is lograthmic, teh amount of CO2 that has been added post industrial revolution is enormous several order of magnitude and there is no downlard trend in this level. I am sure the amount fo GHG that we have added due to anthropogenic activities is huge.
If you are considering the known warm and glacial phase earth has experienced in its geologic past it is true that there is a cyclicity approx. every 10,000 yrs or so earth cools down Pliestocene glaciation is a recent geologic example. But the anthropogenic foot print is apeeding the process of warmin.
Temperature on the earth is rising, snow and rainfall patterns are shifting drastically, and more extreme climate events like heavy rainstorms, tsunami, floods are experiencing often. Activities like burning fossil fuels to generate electricity, heat and cool buildings, and power vehicles or unsafe waste disposal methods are emitting greenhouse gases and short-lived climate pollutants like black carbon into the atmosphere, which cause temperature rising.
Please
Could you first read other very similar questions asked in this topic here at ResearchGate before you ask yours?
And as a first answer I refer you to the most recent United Nations report on climate Change
The so-called IPCC 5th assessment report for free on the web:
https://www.ipcc.ch/report/ar5/wg1/
Nirmala
IPCC does NOT find weather extremes to have increased: their statistics are not sufficient for that conclusion. Also you I refer to IPCC and to another question in this topic here at ReseachGate on "weather extremes"
The truth lies in the storage capacities of molecules. The equipartition therom and molecular degrees of freedom. CO2 is a greenhouse gas because of the additional degrees of freedom it possess in which enegry, in the form of heat from the sun, is stored. Couple this together with the 800,000 year CO2 graph from NOAA, the depletion of our polar ice caps and the "coincidence" of the latest spike with the industrial revolution, and you have an anthropogenic event. Based on these facts and observations I believe it is very real and future generations will suffer dearly if so.
Jason
CO2 does not store energy from the sun. It absorbs radiation that is emitted by the surface of the earth. I also recommend you to read the IPCC-report by the UN and World Meteorological Organisation
https://www.ipcc.ch/report/ar5/wg1/
Climate change is very clearly occurring in historical observations of global climate including the atmosphere, the cryosphere and the oceans. This observation is also supported by theoretical simulations with computer models which show that anthropogenic effects are a key contributor to observed changes. As suggested by Harry ten Brink below, the most authoritative and comprehensive summary of the evidence is in the Intergovernmental Panel on Climate Change reports here: http://www.ipcc.ch/report/ar5/wg1/
Just to feed you with a few CC Indicators:
1. 5 Carbon dioxide (CO2) causing greenhouse gas, through human activities resulting in Agricultural activities, such as deforestation and burning fossil fuels.
2. Global Surface Temperature.
3 The rise up of sea level.
There is abundant evidence of global climate change. For example, in recent years, the temperatures in Hyderabad, India have risen by 10 to 15 degrees Celsius during the wam season and have dropped correspondingly during the cold season, rainfall has diminished (converging to zero) in the western states in the U.S., and so on.
The 50 page report
Indicators of Climate Change for British Columbia 2002:
http://www.env.gov.bc.ca/cas/pdfs/indcc.pdf
gives further evidence of climate climate change.
The authors of this report write:
Both the UN Intergovernmental Panel on Climate Change and the US National
Academy of Science have concluded that the global atmosphere is warming.
They agree, moreover, that most of the warming observed over the last 50
years can be attributed to human activities that release greenhouse gases into the
atmosphere. British Columbia, for example, produced almost 16 tonnes of green-
house gases per person in 1999, most through the burning of fossil fuels for trans-
portation and industrial activity.
Observed climate change in Australia (temperature)
Average temperatures have increased by 1-2 degrees C across Australia since 1910 and warming has been greatest at night and at more inland locations. The frequency of hot nights has increased and the frequency of cold nights has declined. Substantial warming has occurred in the three oceans surrounding Australia. Southern Ocean temperatures have risen since the 1950s to a depth of 1000m in some locations.
Reference
http://www.climatechangeinaustralia.gov.au/recentchanges.php
“We are the first generation that can end poverty and the last generation that can take steps to avoid the worst impact of climate change. Future generations will judge us harshly if we fail to uphold our moral and historical responsibilities.”
Ban Ki-moon, Secretary-General, United Nations
I have written on that
https://www.researchgate.net/profile/Dimis_Poulos
Dear Sati
You are right to some extent, Climate change is natural phenomenon, However, because of human interventions, the change has become so rapid and devastating. That's why, many unforeseen climate change impacts are faced by poor and marginalized people and developing countries the most. its reality now that climate change is happening and its happening so fast, thus we need to act it now...each of us has to think about it.
A New Climate!
"The first ideas of possible anthropogenic (human caused) impacts on climate through greenhouse gas emissions, above all carbon dioxide resulting from the burning of fossil fuels, were introduced at the end of the 19th century. During the 1960s, for the first time, climate models provided us with better insight into what future climate would be like if emissions remain at the same level as then. What has long been an idea, and fifty years ago a first precise quantification of the future climate, has become a reality nowadays. We bear witness to climate change caused by anthropogenic activities on the planet. We are both witnesses and participants in the global experiment of getting the climate system off the energy balance at an accelerated pace, whilst the resulting changes in the various elements of this system can be measured today. The increasing global mean temperature, the melting of the ice sheet, the increasing ocean acidification and the continuous sea level rise are just some of the specifically observed changes within the system...
If this trend of greenhouse gas emissions continues, a trend that has for decades been on the path of very pessimistic scenarios, the climate system will suffer even more dramatic changes, potential losses will become significantly higher and the society will be forced to transform in order to adapt, at least in parts where such is possible. According to climate change scenarios, which suppose a further increase in the concentration of greenhouse gases by the end of this century, the mean annual temperature in Serbia could increase by up to 4°C compared to the value from the mid-twentieth century, while this anomaly could be even higher for individual seasons. In the second half of this century, the climate in Serbia could become considerably more arid with deficits in precipitation during the summer months even up to 50%. The results of climate models indicate that we can expect a further escalation of extreme events. Such drastic climate change would have an extremely negative impact on the eco-systems and the majority of the socio-economic sectors of our society. Many impact studies regarding the effects of possible future climate change on the various sectors clearly point to numerous potential problems in the operation of those sectors in the same capacity as until now..."
http://www.cirsd.org/news/article/a-new-climate
Dear Neeraj,
Thanks for providing sound indicators of climate change.
Planet Earth is about 4.5 billion years old and in this long time there had been periods that were much, much warmer than it is today (e.g. during the time dinosaurs lived on our planet) and also periods that were far colder (ice ages). In other words: it would be strange when the climate would be the same indefinately. This never has been the case. There were also periods when CO2 concnetration was much higher than today. Indeed there was a time when no O2 was in the atmosphere...
Climate change is something that bothers us, because we are effected, because we are there to be bothered. It does not effect Planet Earth in any meaningful way as the planet will be there even if Human aren't anymore (although also Planet Earth won't be eternal). Among many other challenges the scientific mainstream believes that the generation of special gases through the burning of fossil fuels is the driving force for climate change. A few, however, see human contribution little in global warming and some even talk of global cooling.
In RG there have been many contributions that put global warming and global cooling as two different processes. What is different is the outcome of very complex processes. The outcome is either warming or cooling, and to make it even more complex both can happen - in different places.... or at differnt times (a specific place can have warmer summers and colder winters as a resukt of change of the climate....,). How much of this change is contributed by human activies we can discuss and do research about, but it would be strange if only humans have contributed to these changes, or if they would be entirely caused by natural processes - both is very unlikely the case.
Sometimes people think that IPCC does investigate into global warming, but indeed it looks into climate change. The expression global warming is out since many years as it is acknowldeged that it is much more than around temperature change. Global cooling, if it exists is also climate change.
In Germany we can have temperatures in winter of minus 20 degrees Celsius. That is winter and we call this winter weather. Some years winters are mild, other years very harsh, long and very cold. Weather and climate are different things, and the weather is never the same. It changes and also if the sun energy received on January 1 at a particular place would be the same every year (which is not the case as the sender (sun) sends not always the same) it still would result in different weather as the energy received is only one from many, many factors that makes the weather.
In the discussion often people speak of a food crisis because of global warming. I doubt that this is the only possible interpretation. Today we produce considerable more food per capita than a few decades ago. When people are starving then it is usual because of the impacts of wars, civil wars, ethnic tensions, or just because of poverty, but not necessarily because of climate change, at least not so directly as often assumed. Here in the Pacific Island countries the talk of climate change and its impact on food security has been rather dominant, despite this part of the world does not know widespread undernutrition and when we look at malnutrition than we discover that the biggest concern is obesity, and when we would anlyze the causes then we would not find climate change, but MacDonalds and other fast food outlets.
I think that a cooling effect (if it exists) due to reduced sun activity moderates anthropogenic warming impacts, the same other natural impacts on the climate would such as volcanic eruptions etc. We should realise that something as complex as climate has many contributing factors that lead to change.
To assume that everything is caused by humans or everything by natural causes is far too simplistic. For that reason it is rather difficult to make any precise predictions of the future. So both (processes that contribute to warming and such contributing to cooling) not only can happen, but they do, and they always did. What now is sold as new ideas and change to previous scientific knowledge is actually nothing really new other than that one aspect from an extremely complex process is taken out and displayed as the whole truth.
The very early indicators of global warming are sea level rising and oceans' changing...
Dear Eberhart,
Thank you,
I like you expression for a cooling effect (if it exists)...
the both processus, that contribute to warming and to cooling, are they minimum and maximum, but the time of cycles is not the same ...
good day
http://sidaenvironmenthelpdesk.se/wordpress/wp-content/uploads/2013/01/Guidelines-Environment-and-Climate-change-indicators-oct-2010.pdf
https://www.epa.gov/sites/production/files/2016-08/documents/climate_indicators_2016.pdf
http://engineering.tufts.edu/cee/people/vogel/documents/indicators-impacts.pdf
https://www.epa.ie/pubs/reports/research/climate/ERC-6-Climate%20Change-web-ready3.pdf
How do we know our climate is changing permanently, rather than just going through a normal period of flux? Let’s look at 10 major changes scientists have seen in our climate system to help set the record straight.
1. AIR TEMPERATURES OVER LAND ARE INCREASING.
It’s clear that weather stations on land show average air temperatures are rising, and as a result, the frequency and severity of droughts and heat waves are increasing. Intense droughts can lead to destructive wildfires, failed crops, and low water supplies, many of which are deeply affecting southern areas of the United States and other parts of the world.
2. AIR TEMPERATURES OVER OCEANS ARE INCREASING.
Roughly 70 percent of the world is covered by oceans, so you can understand how hotter air over them could make a vast difference in the climate system.
Oceans evaporate more water as the air right near the surface gets warmer. The result? More floods, more hurricanes, and more extreme precipitation events.
3. ARCTIC SEA ICE IS DECREASING.
Satellite images from space show that the area covered by sea ice in the Arctic is shrinking, and it’s continued a downward trend for the past 30 years. The Arctic ice cap grows each winter when there’s less sunlight, and shrinks each summer when days are longer, reaching its lowest point of the year in September.
Some research suggests that the Arctic could lose almost all of its summer ice cover by 2100, but others believe that it could melt completely much sooner than that – in just a few decades.
4. GLACIERS ARE MELTING.
The disappearance of glaciers is one of the clearest signs of climate change. People who rely on melting glacier water are facing shortages, and in many regions, the situation is only getting worse.
In a world unaffected by climate change, glacier mass stays balanced, meaning the ice that evaporates in the summer is fully replaced by snowfall in the winter. However, when more ice melts than is replaced, the glacier loses mass. And the people who depend on melting ice for water to support their farming and living needs are deeply affected.
5. SEA LEVELS ARE RISING.
Sea levels have been rising for the past century. And the pace is only increasing in recent years as glaciers melt faster and water temperatures increase, causing oceans to expand. You can imagine how this would affect the almost 40 percent of the US population that lives in a highly populated coastal area. Let’s not forget that eight of the 10 largest cities in the world are near a coast.
Consider how many millions of people are at risk as sea levels rise, storms intensify, and more extreme flooding occurs. Additionally, marine life is threatened as salt water intrudes into fresh water aquifers, many of which support human communities and natural ecosystems.
6. HUMIDITY (EVERYONE’S FAVORITE) IS INCREASING
More humidity means more water vapor is in the air, making it feel stickier in hot weather. Water vapor itself is an important part of the water cycle, and it contributes to the earth’s natural greenhouse effect. Air conditioners have to work much harder to make us feel cool as the amount of water vapor in the air increases. Which means more energy use, which can in turn contribute to more climate change. Lose-lose.
7. OCEAN HEAT CONTENT IS INCREASING.
The ocean stores and releases heat over long periods of time. This is a natural and important part of stabilizing the climate system. Natural climate patterns (think, El Niño) occur regularly because of warmer ocean waters and influence areas like regional climates and marine life.
But it’s when short-term, natural climate patterns like El Niño occur at the same time as oceans are becoming warmer and warmer that we know that larger changes are happening. The increased heat content leads to higher sea levels, melting glaciers, and stress to marine ecosystems.
8. SEA SURFACE TEMPERATURE IS INCREASING.
Measuring instruments show that water temperatures at the ocean’s surface are going up. To some extent, this is a normal pattern: the ocean surface warms as it absorbs sunlight. The ocean then releases some of its heat into the atmosphere, creating wind and rain clouds.
However, as the ocean’s surface temperature continues to increase over time, more and more heat is released into the atmosphere. This additional heat can lead to stronger and more frequent storms like tropical cyclones and hurricanes.
9. SNOW IS DECREASING.
Satellites show areas covered by snow in the Northern Hemisphere are becoming smaller. Snow is important as it helps control how much of the sun’s energy Earth absorbs. Light-colored snow and ice reflect this energy back into space, helping keep the planet cool.
However, as the snow and ice melts, it’s replaced by dark land and ocean, both of which absorb energy. The amount of snow and ice loss in the last 30 years is higher than many scientists predicted, which means the Earth is absorbing more solar energy than had been projected.
10. EARTH’S LOWER ATMOSPHERE TEMPERATURE IS INCREASING.
The lowest layer of the atmosphere, called the troposphere, is the layer we’re most familiar with – it’s where we live and where our weather occurs. Satellite measurements show that this lowest layer of the atmosphere is warming as greenhouse gases build up and trap heat that radiates from the Earth’s surface.
Scientists tell us that human activity, particularly the burning of fossil fuels, caused this increase in atmospheric temperatures. In fact, carbon dioxide levels have increased about 40 percent since the Industrial Revolution began in 1750. And unless we put a stop to this trend as soon as possible, these levels – and temperatures – likely will increase even more.
Source:https://googleweblight.com/i?u=https://www.climaterealityproject.org/blog/10-indicators-that-show-climate-change&hl=en-IN
Dear Vishwambhar Prasad Sati, I have got an interesting document about indicators of climate change published in 2016. I hope it will helpful.
Carbon dioxide levels hit historic high. "We are continuing full speed ahead with an unprecedented experiment with our planet". From THE WEEK, May 25, 2018.
Thank you for enlightening me sir. Yes you are right that carbon emissions hit historical during the recent years.
Atlantic current is slowing. The likely culprit is climate change.
Please see the attached article.
As climate change continues to heat up the oceans, many species of fish are expected to decrease considerably in size. This could hit the fishing industry hard.
See the attached article.
3 Trillion metric tons of ice lost from the Antartic Ice Sheet from 1992 to 2017.
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