Yes, in short.

In fact, it's not even possible, but scientifically sound too: we know that global warming is bound to increase the probability of extreme events. (Now individual episodes are a different question.)

I don't think you can blame global warming for a specific tornado or heatwave because global warming is a measure of overall temperature whole over the globe. I think pole ice melting is a better indicator than other extreme events.

However, what is interesting is that the general population is more likely to believe in climate change after being exposed to such extreme events...

You can't attribute individual events with 100% certainty, but you can make statements about how probable it is that extreme events are due to global warming, as opposed to natural variability. Note also that there is a lot of nuance to how an "extreme event" is defined -- heat waves? cold snaps? tornadoes? Those are all really different things! the RealClimate blog has a pretty good overview with interesting references: http://www.realclimate.org/index.php/archives/2012/08/extreme-metrics/#more-12692

I wouldn't claim flood or drought as extreme climatic event, they are natural perturbations. The extreme climatic events are clearly defined, please visit: http://cccma.seos.uvic.ca/ETCCDI/list_27_indices.shtml. On one hand, the variability of extreme climatic events are clear indicators of climate change now a days, several studies have already been published; but they are not necessarily consequences of global warming. On the other hand, the natural perturbations clearly follow the cause and effect relationship with climate change. Even the extreme perturbations like cyclones are also being proved to be the consequences of global warming.

I will add my voice to the other comments above. Global warming cannot be blamed for extreme weather per say. However, the right question would rather ask about the frequency and severity of "outlier" events, such as strong hurricanes or prolonged heat waves. Although the science remains uncertain about this, there is emerging evidence that global warming indeed influences the frequency and severity of such events. See these studies, by top people in the field:

Tropical cyclones and climate change, by Knutson et al. Nature Geoscience 3, 157 - 163 (2010), Published online: 21 February 2010 | doi:10.1038/ngeo779

Perception of climate change, by Hansen et al.

http://www.pnas.org/content/early/2012/07/30/1205276109.full.pdf

Global Warming

Nature turns out, between natural processes and human actions, about 200 billion tons of carbon dioxide (CO2) into the atmosphere per year. Human actions are responsible for about 7 billion tons (less than 5%). One of the main goals of the RIO +20 is to convince the so-called developed nations to reduce their emissions by 20% of so-called greenhouse gases by 2020, which amounts to about 1.4 billion tons, 0.7% of total emissions of 200 billion tonnes / year, a very small quantity that does not interfere with absolutely nothing on climate change which, incidentally, are the 3.8 billion years.

Remember that only the eruption of Pinatubo in the Philippines in 1991, turned out greenhouse gases in the atmosphere equivalent to 300 years of human activity in the world at 2010 levels. The Icelandic volcano Eyjafjallajökull poured in 2010, material polluting the atmosphere, the equivalent of 1000 years of human activity in Europe, the levels of the same year. The Chilean volcano Puyehue, in 2011, turned in the air the equivalent of 5000 years of human activity in the city of São Paulo, also at 2010 levels. Outside the sum of all other volcanoes that erupt every year, causing the same phenomena but on a smaller scale.

Again I emphasize, on this information, there is a hysteria on this subject in relation to human actions against climate change. The focus should be turned to other types of pollution, such as water by heavy metals used in pesticides, unsustainable activities such as overfishing and ocean waterways, deforestation, reforestation without compensatory measures, the non-preservation of water sources, lack of public policies awareness of the importance of recycling and promotion of selective collection in neighborhoods, public lighting with low efficiency light bulbs etc ....

From the birthplace of meetings like this RIO +20, much has changed for better and for worse.

To better - The discovery, by serious scientists, that CO2 is a gas unfairly demonized and that he alone would interfere very little an alleged global warming and that is a mere supporting role in the greenhouse effect, a natural phenomenon that enables life on the surface land.

The recognition by the public that there are current policies and business who want to take the issue to earn their own advantages. Ex: vehicle inspection programs in cities like São Paulo, which has proved useless but still there, filling the pockets of many political campaigns and funding on the basis of party donations; lobbies of large companies in emerging countries to pass laws that favor (eg automakers), the emergence of NGOs picks, taking advantage of the situation and make money to stay around spreading nonsense; business lobbies upon bodies on legislation on environment etc ....

For worse - The perception on the part of developed nations said that the matter politically CO2 could be used as bargaining chips to emerging nations that do not attain the same level of their development. With that, these emerging contain its consumption of raw materials and commodities, retard its growth and perpetuate the same strategy as satellites.

Realize that one of the subjects of this meeting is the aversion to consumerism, ie, we must consume less in the name of sustainability while "developed" preach the increased consumption in their countries to boost the economy and, therefore, out of the crisis. Explain this paradox.

It also has terrorism with water. It is not today that mega-corporations and big business groups (with the consent of political groups privatas) are willing to take care of the water and turn it into a commodity, for that use the press (which sells to such) and NGOs, precisely to go putting the head of each, gradually, that water is a finite resource and that one day it will end. First, water is a renewable resource, since, no matter who is in the middle, in the presence of the sun it evaporates and turns into rain, and thus by a process of natural filtration. The only thing that makes it unusable for drinking water is contaminated by heavy metals, these metals is able to bind to point at the molecular level to combine with hydrogen atoms and oxygen by changing its chemical structure preventing water to purify the evaporation process. Other than that, we already have technologies that are independent of natural purification. Of course this does not exempt us of using water treated with discretion and responsibility for, besides man, is a resource that may become inadequate before the population growth in an area, making it necessary to get it going farther and farther.

To conclude, one of the major problems facing Brazil's urban concentration. This type of social phenomenon makes you create megalopolises with a high degree of impermeability water causing it to turn into heat islands leading to the feeling that the world is warming, when in fact it is a local phenomenon.

Measures to contain this process would: prohibit the construction of buildings over ten stories; afforestation of the whole city; exempt areas like gardens planted in homes and business property tax, encourage the use of public transportation, bicycles and electric vehicles without stunt rights of others; require transportation companies to use clean fuel powered engines, electric motors or adapt diesel fuel low sulfur content.

For that... It is possible to blame the governments, too

The following recent paper by James Hansen et al. in the US Proc Natl Acad Sci journal is very relevant.

James Hansen, Makiko Sato, Reto Ruedy

‘Perception of climate change’

PNAS ∣ Published online August 6, 2012 ∣ E2415–E2423

www.pnas.org/cgi/doi/10.1073/pnas.1205276109

I wish to bring to your notice our past paper uploaded on RG "Onset of climate change". The extreme events occur more during transition phase, when system changes from one stable climate phase to another. We worked on Last glacial - Holocene transition. Looking at global records we understood that Climate transition (Last Glacial to Holocene) took about 7ka. In this 7ka we had several climatic events.

If we look with this perspective for present day extreme events, it leads us to infer that ongoing extreme events suggests we are still in Holocene- Neoholocene transition popularly marked by Anthropocene!!

Good question and difficult to answer. Here in the Pacific Islands we have statistically a number of tropical cyclones in a cyclone season.

This of course is not just since everybody talks of climate change; it might be that as a result of cliamet change the cyclones are stronger as more energy is stored in the ocean water which increases in temperature. However the mechanisms are very complex and surely not as straight forward as people often create impressions.

I totally agree with Dr. Kenneth that islands can not be considered as static. The Survey of India Department is constantly monitoring the atoll islands (Lakshadweep Island) in Arabian Sea using DGPS for possible drifting or sinking of these islands.

Not in every case

We should all understand that the concept of "Extreme weather" is not only in the light of "Hot" conditions but also "Cold" condition. There is a gradual paradigm shift in seasons, across the globe. While some places are become unbearably hot, other places are becoming too cold. Like i always say... "The effect of global warming is a complex mix" and many of the aftermath effect cannot be clearly predicted with scientific modeling, but becomes glaring with time. The earlier the world begins to reduce carbon imprints the best for the planet.

"Climate Change" is primarily a natural phenomenon. Human has minimum control on it. Of course, we have to reduce the carbon imprints, so that some regional/local environmental problems can be minimized.

Regards

yes. It is

Gore's home energy use averaged 19,241 kilowatt hours (kWh) every month !!!

What to say?

Regards

In Documentary Movie: "An Inconvenient Truth, 2006, by Davis Guggenheim” that written by Al Gore 12 years ago and received many different awards worldwide that made it even as an educational resource:

The impacts of global warming showed and described in a very typical method by comparison the photos from the past to the present. In this movie, the increase in population mentioned as a main factor in global warming and according to that, the temperature records showing that, the ten hottest years ever measured all occurred recently. The increase in phenomenon such as disasters, hurricanes and storms, melting glaciers and rising the water level are also matched by global warming.

Some of the paradoxes in the documentary movie by an environmentalist:

- At least Al Gore could use an electrical or hybrid car as he mentioned during his film. Because using a “Mercedes Benz with driver” by himself and then talking about the air pollution by cars is funny!

- Al Gore showed his father’s tobacco lands that was abandoned in many years by himself. This also can cause erosion and environmental damage, because the landuse changed by human and he did nothing about it and just showed an old tobacco warehouse that was still there.

- .....

At the end, the movie focused to the forces on the researchers by the governments to change their results about the CO2 levels and this type of research. Al Gore finally mentioned: “it is difficult to get a man to understand something when his job depends on not understanding it”!

Best Regards

hello all

actually it is good question, i interested all answers especially from prof kenneth.

it is hard to blame extreme weather in large scale. in small scale yes will affect and in general it is part of global warming relatively

regards

Extreme weather (heatwave, flood, drought, etc.), must be considered besides other factors such as the human activities, urbanization, population growth, etc. and not just as a result of global warming.

- The annual rainfall about 200mm in a city with 10,000 population in 100 years ago might not recorded as drought but when the population of the same city reach to 1 million, even 300mm annual rainfall means drought.

- The extreme weather like storm in a forest area might not cause flood but after cutting all trees and after urbanization the same rainfall will cause a flood.

- In 100 years ago, the extreme weather such as high temperature in a summer was tolerable in a city since there was more green area and plants and the evapotranspiration by plants can decrease the temperature (up to 12°C, EPA report, 2015) and stop the heat island effect. However, after more urbanization, the temperature at the same area will increase. Because without plants and the heat island effect, the temperature will rise and even the reflection of solar radiation by soil surface is more than asphalt, roofs, etc.

The average annual rainfall and average temperature in some basins not changed too much during the previous decades, but the rivers and lakes become dried recently. It is not because of the “Global Warming” it is because of “Global Human Activities”.

Since all cities are already full of populations, so the solution is not stop urbanization and stop human activities. The best solution might be decrease of the global impacts of 8 billion people and decrease of the global impacts of human activities on the environment.

Regards.

Research Proposal New method for reducing water and energy consumption by conf...

One of the premises of serious climate research is to put in the head that the climate is dynamic and does not follow algorithms.

Climate change is and has always been permanent, subjecting the planet to great extremes since the beginning of the existence of the atmosphere.

Based on IPCC AR1-5, It can be right!

Dear Kenneth

I am confused about the temperature data record. Based on your data the average temperatures after all these years not changed but base on NOAA changed.

NOAA, 2016:

• In U.S. Since 1901, the heat waves in the 1930s remain the most severe heat waves in the U.S. historical record. But the average surface temperature across the contiguous 48 states has risen at an average rate of 0.14°F per decade (see Figure 1). Average temperatures have risen more quickly since the late 1970s (0.29 to 0.46°F per decade since 1979). Eight of the top 10 warmest years on record for the contiguous 48 states have occurred since 1998, and 2012 and 2015 were the two warmest years on record.
• Worldwide, 2015 was the warmest year on record and 2006–2015 was the warmest decade on record since thermometer-based observations began. Global average surface temperature has risen at an average rate of 0.15°F per decade since 1901, similar to the rate of warming within the contiguous 48 states. Since the late 1970s, however, the United States has warmed faster than the global rate.

https://www.epa.gov/climate-indicators/climate-change-indicators-us-and-global-temperature

Regards

Pirouz