Attribution of recent climate change is the effort to scientifically ascertain mechanisms responsible for recent changes observed in the Earth 's climate, commonly known as 'global warming '. The effort has focused on changes observed during the period of instrumental temperature record, when records are most reliable; particularly in the last 50 years, when human activity has grown fastest and observations of the troposphere have become available. The dominant mechanisms are anthropogenic, i.e., the result of human activity. They are: increasing atmospheric concentrations of greenhouse gases global changes to land surface, such as deforestation increasing atmospheric concentrations of aerosols.
There are also natural mechanisms for
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Between the start of the Industrial Revolution in 1750, and the year 2005, the increase in the atmospheric concentration of carbon dioxide led to a positive radiative forcing, averaged over the Earth 's surface area, of about 1.66 watts per square metre .
Climate feedbacks can either amplify or dampen the response of the climate to a given forcing.
In the absence of forcings imposed on it, the climate system will still show internal variability . This internal variability is a result of complex interactions between components of the climate system, such as the coupling between the atmosphere and ocean . An example of internal variability is the El Niño-Southern Oscillation.
Detection vs. attribution
Detection and attribution of climate signals, as well as its common-sense meaning, has a more precise definition within the climate change literature, as expressed by the IPCC. Detection of a climate signal does not always imply significant attribution. The IPCC 's Fourth Assessment Report says "it is extremely likely that human activities have exerted a substantial net warming influence on climate since 1750," where "extremely likely" indicates a probability greater than 95%. is absorbed and emitted naturally as part of the carbon cycle, through animal and plant respiration, volcanic eruptions, and ocean-atmosphere exchange.
The high-accuracy measurements of atmospheric CO2 concentration,
The industrial revolution began in the 17th century and made significant change in the world. An era was over and the new one was beginning. The revolution has advantages and disadvantages. Rising of living standards, improving of health, lifetime and trade system are its advantages. On the other hand, manufacturing has caused major problems such as deforestation, excessive use of fossil fuel sources, irresponsible industrialisation and agricultural development. These changes have increased world’s atmospheric concentration of water vapour, CO2, CH4 and other gases (Stocker, 2013). These gases capture part of energy receiving from sun and trap this heat inside atmosphere that causes rising temperatures on the earth’s surface. Naturally, for continuation of life these gases are necessary, but result of the human events these gases has produced more than plants and environment need (Robins, 2016). Also, we call them Green Houses Gases because they have the similar effect like the ‘greenhouses’ utilised to increase condition of vegetables.
According to this Chapter, the cause of these climate changes came from forcing. Forcing is any ongoing process or discrete event that alters the energy of the system. Examples of natural forcings include volcanic eruptions, periodic shifts in the Earths’s orbit and changes in the sun’s
During the past several hundred years, civilization has made rapid progress in industries like air travel, automobiles, and energy production. These developments were made without consideration of the long-term effects that their emissions may have on the planet. Changing weather patterns are now wreaking havoc around the world, and scientists attribute this to human-caused climate change. During President Obama’s State of the Union address in 2015, he stated that, “No challenge poses a greater threat to future generations than climate change,” (“Remarks by the President”). Warming temperatures caused by anthropogenic climate change have disastrous consequences that pose a threat to humanity and the environment.
on, there are other, natural forcings that have effects on the global climate. A few of these
But many climate scientists will tell you that this change in climate is due to humans and their activities. It is said that humans release greenhouse gases and “if emissions continue unchecked, they say the global warming could ultimately exceed 8 degrees Fahrenheit, which would transform the planet and undermine its capacity to support a large human population” (Gillis, 2015). To make it easier to understand, as sunlight reaches the Earth’s surface there are two things that can be done, one; it can either be reflected back into space or two, it can be absorbed by the Earth. Once the Earth absorbs the sunlight, it then releases some energy back into the atmosphere as infrared radiation, also known as heat. Then these greenhouse gases tend to act like a “blanket,” therefore making the Earth warmer than it would be otherwise. This process is what we call the “greenhouse effect.” The reason scientists say that climate change is caused by humans is that it’s simple, humans drive, cook food, and even heat or cool their homes, which release gases such as, carbon dioxide (CO2), methane (CH4 ), and water vapor (H2O).
Global warming is defined as the recent increase in the world 's temperature that is believed to be caused by the increase of certain gases (such as carbon dioxide) in the atmosphere. There are many different theories on whether global warming is similar or not to climate change. Simplistically, climate change is different because climate change is defined as a change in global or regional climate patterns or, in particular, a change apparent from the mid to late 20th century onwards and attributed largely to the increased levels of atmospheric carbon dioxide produced by the use of fossil fuels, having been measured over long periods of time, due to the changes in Earth’s orbit and organic carbon which reflect sunlight. Global warming and climate change are not to be confused because global warming is caused mainly by anthropogenic factors like the emission of carbon dioxide gas and use of fossil fuels whereas climate change is completely natural, however, according to Milan Radovanovic, “it is clear that the anthropogenic factors dominate the increasing temperature and the natural ones have the maximum influence…” (Radovanovic). Therefore, “the contribution to global warming from natural forcings and from natural internal variability is in the range between -0.2 to 0.2 [degrees] celsius over the period 1951-2010…” (Radovanovic). Natural factors have had the most effect on global temperature in the past 59 years totaling a 0.4 degrees celsius increase in
Climate change can be defined as a significant change in the “average weather” of any given region sustained in the long-term and can be caused by Earth 's dynamic processes, external forces including variations in sunlight intensity, and also by human activities (USEPA, 2014).
In the last 100 years, Earth’s average temperature has risen by 1.4°F. The rising global temperatures have caused changes in weather and climate. Global warming refers to the ongoing rise in the average temperature near Earth’s surface. This is causing a climate change, which refers to any significant change (major change in temperature, precipitation, or wind patterns) in the measures of climate lasting for an extended period of time (several decades or longer). Due to this, it is projected that the temperature will rise from 2 to 11.5°F in the next hundred years (US EPA, 2014). The “drivers,” which are the principal causes making this occur, are very controversial. It is debated whether a change in temperature is due to the work of
In order to understand the issue of global warming (also referred to as climate change), you must first understand what it means and how it happens. Global warming is a result of a process known as the greenhouse effect, in which the light and heat from the sun are trapped in the Earth’s atmosphere by greenhouse gases; which subsequently raises the average temperature on Earth. The greenhouse gases responsible for this process are carbon dioxide, methane, nitrous oxide, chlorofluorocarbons, and tropospheric ozone, all of which are released into the atmosphere through naturally occurring processes (Warrick, R. & Farmer, G., 1990).
One of the main reasons that earth’s temperatures are rising are due to greenhouse gases. Greenhouse gases are created when humans burn fossil fuels such as coals, natural gases, and oils to produce heat or electricity. These gases are then capable of trapping infrared radiation sent by the sun. Once these
• Carbon dioxide (CO2) is a greenhouse gas that warms the atmosphere. • Since pre-industrial times, atmospheric CO2 concentrations have increased from about 280 parts per million (ppm) to over 380 ppm. Current concentrations of CO2 and other greenhouse gases are unprecedented in at least the last 650,000 years, based on records from gas bubbles trapped in polar ice. • Independent measurements demonstrate that the increased CO2 in the atmosphere comes
The human race all around the world wonders if the climate is changing due to human activity or if it is just a natural occurrence. At certain parts of the Earth's surface, the climate can be observed much differently than other locations. As the years go by the average temperature of the Earth increases by little intervals. There are several different reasons why people believe the climate is changing every year. However, the increase of worldwide population and production of heat to the atmosphere is due to the increase of human activities that take place on a daily basis. Human activity is the main cause of the global climate change. The human impact on climate exceeds any known changes due to natural processes. The impact of this human activity is often misunderstood when looking at climate change.
Researches reveal that natural events as well as human related activities contribute to changes in average global temperatures. AtKisson affirms that global warming is basically a result of increased emission of greenhouse gases into the atmosphere. This atmospheric carbon dioxide (co2) comes from anthropogenic (caused by humans) sources. The concentration of greenhouse gas carbon dioxide, nitrous gases, and methane in the atmosphere has increased evidently due to human activities since 1800. NASA’s article adds:
Current data reveals that the concentration of Carbon Dioxide in the earth's atmosphere is approximately 387 parts per million, which is roughly a 31% increase in the period 1750 to 2009. Consequently, it is evident that such increases in temperatures have caused a warmer planet (7). It is also evident that it is impossible to reverse the developments of industrial revolution. This means that as the advancements of industrial revolution continue and as energy demands increases, it is possible that this trend of climate change will continue for decades to come (McAloon, 8). The consent of the climate research community is that it most likely already affects climate noticeably and will compel significant
Scientists have discovered 'climate forcing’s ' influence variations in climate systems and based on the depth and period of such forcing’s the adjustments to climate may be in a shorter or longer earth cycle. Natural forcing’s like variations in earth 's orbit, solar variation, volcanic eruptions and motion of tectonic plates have influence on the Earth 's climate