Why is extreme weather increasing?

Question

I think we are all familiar with the hypothesis that a warming world will "load the dice" and increase severe weather events, prolong droughts, cause more snowfall, intensify hurricanes, etc.

Let's look at global temperature and sea surface data from the last 10 years: http://www.woodfortrees.org/plot/hadcrut4gl/from:2003/plot/hadcrut4gl/from:2003/trend/plot/rss/from:2003/plot/rss/from:2003/trend/plot/hadsst2gl/from:2003/trend/plot/hadsst2gl/from:2003

Let's even accept that those negative trends don't say much about long term warming. That's not what this question is about.

The question is, how can severe weather be increasing in the past ten years if warming has not in the atmosphere or in sea surface temperatures?

Answer 1

Rolando, JeffM, Big Gryph, Gcnp, and even DaveH (not generally pro-science) all offer intelligent well-informed answers. Good job guys...

EXCEPT

You ought to know better than to waste your time that way.



I feel strongly that climate modelling is heavily overemphasized by anti-science deniers. After all, who nitpicks about "predictions" when buying fire insurance? Nevertheless, here I very confidently predict that Ottawa Mike will utterly ignore all your answers

EXCEPT

That he may well use them to come up with a less stupid deceit-intended fake question next time he picks this subtopic for his daily recycling of Wattsup's anti-science disinformation.

Answer 2

Too bad your premise is false to begin with.



Hurricanes for example:



The premise of your question is false, the frequency of "unusual" events are well within historical norms and some are actually in a downward trend. The only thing that happens more is the reporting and the misinformation. Hurricanes for example. 19.2 per decade average over the century from 1850-1950 and 13.7 per decade for the time period 1951 to 2004. Average of 6.1/decade major hurricanes 1850-1950 and 5.2/decade 1951-2004. Damages will always increase due to inflation and increase in coastal buildup of cities. Additionally, only three of the ten decades from 1850 to 1950 had hurricanes in the SAME OR LOWER numbers than the HIGHEST number of hurricanes in a decade from 1951-2004.



Source(s):

http://www.nhc.noaa.gov/pastdec.shtml

Answer 3

Has extreme weather increased in recent years? The science is still unsettled on whether climate change has resulted in more intense hurricanes, so let's restrict our attention to tornadoes and heavy rain. There is evidence that global warming has caused an increase in very heavy precipitation events--the kind most responsible for major floods. However, there is no evidence that climate change has caused in increase in tornadoes and severe thunderstorms, though preliminary research suggests this may occur late this century.



However, this increase may be entirely caused by factors unrelated to climate change:



Population growth has resulted in more tornadoes being reported.

Advances in weather radar, particularly the deployment of about 100 Doppler radars across the U.S. in the mid-1990s, has resulted in a much higher tornado detection rate.

Tornado damage surveys have grown more sophisticated over the years. For example, we now commonly classify multiple tornadoes along a damage path that might have been attributed to just one twister in the past.

Given these uncertainties in the tornado data base, it is unknown how the frequency of tornadoes might be changing over time. The "official word" on climate science, the 2007 United Nations IPCC report, stated it thusly: "There is insufficient evidence to determine whether trends exist in small scale phenomena such as tornadoes, hail, lighting, and dust storms."



Furthermore, we're not likely to be able to develop methods to improve the situation in the near future.The current Doppler radar system can only detect the presence of a parent rotating thunderstorm that often, but not always, produces a tornado. Until a technology is developed that can reliably detect all tornadoes, there is no hope of determining how tornadoes might be changing in response to a changing climate. According to Doswell (2007): I see no near-term solution to the problem of detecting detailed spatial and temporal trends in the occurrence of tornadoes by using the observed data in its current form or in any form likely to evolve in the near future.

Answer 4

At a simple intuitive level I would expect the weather to be more extreme. Here is my 'back of then envelope' take on it.



We have more energy in the climate system now than we did, say 50 years ago. We know this from 2 simple measures; atmospheric temperature, but more significantly, total ocean heat content.



The Earth is kept at its odd temperature by warming due to greenhouse gasses, countered by heat loss through the poles. It is a huge 'tropics to poles' heat engine.



If there is more energy in the whole system, then the heat transfers, oceanic and atmospheric should speed up and become more turbulent. This should increase weather variability.



Edit OM. "However, I am framing this around the energy change in the last ten years". Sure, but even though the atmospheric temp has levelled, the total Ocean Heat Content is still rising.



Here's another thought about extreme weather for you. Which of these two,cases has greater heat loss?

- earth with evenly distributed heat at 15deg,

- earth with half at 13deg and the other half at 17deg

The latter, because radiation is at the fourth power of temperature. The more unevenly heat is distributed across the earth, the greater is the heat loss through radiation.



Another point to make about extreme weather events is that they release huge energy to space. Big storms are made of a lot of cloud... and that's a lot of heat transported from the ocean (by evaporation) to the cloud body (latent heat released by condensation). Cloud both reduces heat gain to the earth, by reflection, and transports heat to space... radiated out of the cloud top. The bigger the storm, the more the earth is cooled.



Essentially, the climate moves to moderate the effect of any imposed change.

Answer 5

As the troposphere warms which it has been noticeably over the last ten years (3 decades really), there is more evaporation and that moisture fuels bigger storm activity Some areas will get the prolonged heat waves and drought while others will get the raining and flooding.



The 2011 tornado season for the US was indeed significant. It is easy to blame this on GW but the 2012 season was pale in comparison. But 2012 brought a great deal of forest fire activity and drought. Drought was felt over a large portion of the contiguous states



It will be many years before these could be attributed to GW although I believe they are a consequence of this. The drought will stay with us and has been increasing here in the US and some other areas. Unfortunately I think we will see forest fires again for US and Australia similar to 2012.

Flooding for Bangladesh and the Philippines and increased ground/drinking water salinity for low lying island nations will be the case as well

Answer 6

It's because the number you've plotted is a global average and the regions of the ocean that provide moisture for midlatitude storms have gotten quite warm.



http://pielkeclimatesci.files.wordpress.com/2012/08/sst-anom.gif



It's not complicated. Mix up cold water from the deep ocean, surface temperature in those regions go down (bringing down the global average), but globally over all compartments the system is heating up. I'm not sure why you see monsters everywhere you look without checking to see if it isn't just a coat on a chair. I guess if you're scared of the dark that happens a lot.

Answer 7

The energy is not 'hidden' in the deep oceans as much of it has been found. Why do you keep stating the old myth that the energy is 'hidden'?



In the following link look at the measurements for 0-2000m compared to the measurements for 0-700m.



http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/



What are you stating is false. The graph you linked to, that of HadCRUT4, only measures surface temperatures. Surface temperatures over short time scales are mainly controlled by the ENSO cycle.



http://www.esrl.noaa.gov/psd/enso/mei/



If you'll look at both the graph you posted as well as the graph for the ENSO index you will see a about 4 years of moderate El Ninos, from where you started your time series, to two powerful La Ninas with a short moderate El Nino separating them. The energy is not 'hidden in the deep ocean'. The energy exists within the ENSO cycle with assistance from the PDO, which is what controls ENSO variability on longer time scales.. On longer time scales then you can say the energy has been cast into the deep ocean. On these short time scales, though, it is very doubtful. And the ENSO cycle are one of the major controllers of weather on a yearly and region by region basis.



https://www2.ucar.edu/atmosnews/research/5566/el-ni-o-and-climate-change-coming-century



"Climate change is not expected to affect the extent or frequency of the El Niño/Southern Oscillation (ENSO) over the 21st century, but it could worsen its impacts...However, the warmer and moister atmosphere of the future could make ENSO events more extreme."



Edit: It has been stated that "If you add more energy to the system you increase volatility" in a previous post. Added heat content means more energy is in the system. They are most likely talking about added energy, greater precipitation due to more moisture content, a changing water cycle, and so on. When I say "Energy exists within the ENSO cycle" I am talking about heat distribution. Measuring the heat in only one part of the system while ignoring other parts of the system does not, logically, mean that the entire system is following that single measurement.



An El Nino is characterized by more frequent precipitation extremes in some parts of the world and droughts in others while a La Nina event is characterized by precipitation extremes and droughts in other areas of the world. A redistribution of heat and weather cycles is the cause.



http://www.soest.hawaii.edu/mguidry/Unnamed_Site_2/Chapter%204/Chapter4D.html

Answer 8

Well, I'm glad to see that you accept that short term trends aren't too helpful, but wouldn't you also have a similar problem with weather trends over this period?



If anything, I would have thought weather trends would be even more uncertain over 10 years than temperature trends.

Answer 9

We have had no extreme weather (extreme reporting yes) unless you count the last few northern hemisphere winters, which I consider natural global cooling,

Weather is caused by fluids, atmosphere/oceans, all engineers know fluids are chaotic systems which you cannot model or predict.

Answer 10

You are such a denier. Yesterday it rained where I live. It rained. On Vancouver Island. In April.





I am not making that up.





http://www.youtube.com/watch?v=mZEMRAWaVr8





Edit: Thumbs down from the anti science holocaust deniers already. Typical. Consider this, it never once rained in April on Vancouver Island before 1970 (don't look that up because the deniers have hijacked the internet) and now it does . Coincidence? Yeah, if you're a denier I guess it is. To rational human beings who live in reality it proves Catastrophic Global Warming is real.

Answer 11

According to "Inconvenience Truth" the world only had until 2008 to stop global warming. Now it is TOO LATE.



90% of humanity will die HORRIBLE deaths from floods, hurricanes, droughts, blizzards, asteroids, tsunamis and earthquakes.



Only the Lear jet people like Michael Moore and Al Gore will survive the coming climate APOCALYPSE in their underground mansions.

Answer 12

It's not, it's just easier for us to see and record it now than it used to be.