A lot of verbage about global warming/climate change is worse than useless because the parties are using terms whose meaning is vague or equivocal, and thus no meaningful interaction occurs. Alarmists/activists claim climate change is real, man-made, and dangerous (Obama tweet). Skeptics/doubters respond that climate is always changing, has been both warmer and cooler in the past, long before humans did anything.

In addition, climate confusion causes statements like this one recently in the CBC: Gatineau flooding ‘tip of the iceberg,’ climate scientist warns

Swollen rivers and streams have threatened hundreds of homes in the Outaouais thanks to recent heavy rainfall — three times the normal amount since April 1.

University of Ottawa climate scientist Paul Beckwith says that’s due to a changing climate, and says we’re seeing its effects “on a day-to-day basis” in weather patterns.

Beckwith points to an increase in extreme weather events across North America as proof. “We’ve changed the chemistry of the atmosphere and the oceans with our greenhouse gases, so we’re seeing the consequences of this now,” he added. “It’s only the tip of the iceberg, so to speak.”

Such reports mislead people to think of the climate acting like some kind of agent causing the weather to change in ways unfavorable to us. That confuses the relation between climate and weather, as we shall see below.

What is “Weather”?

Fortunately in science things get defined not theoretically but by observations and measurements. In science, weather is defined as the behavior we measure on a daily basis. In fact today’s automated weather equipment monitors the weather constantly. Let us consider an operational definition of weather to be the variables for which data is reported into global databases.

 

Each National Weather Service has its own additional particulars they track, but the common global definition of weather can be seen in the defined elements from the ECA&D weather data dictionary (European Climate Assessment & Dataset)

Weather Measurement Elements

What is weather: Eight variables are measured globally–Sunshine, Sea Level Pressure, Humidity, Cloud cover, Wind, Precipitation, Snow Depth, Temperature. With multiple measures of some variables, weather datasets consist of 13 common elements.

Sunshine (SS) in units of 0.1 hour. Total daily SS plus measures of hours for intervals during the day.

Sea Level Pressure (PP) in units of 0.1hPa Daily average PP plus measures for specific times and parts of the day.

Humidity (HU) in units of 1% of relative humidity. Daily average HU plus measures for specific times and parts of the day.

Cloud Cover (CC) in oktas (0 being clear sky, 8 being completely overcast). Daily average CC plus measures for specific times and parts of the day.

Wind Direction (DD) in degrees azimuth for the wind source (that is, a southerly wind comes from 180 degrees.) Daily average DD plus measures for different times of day, and the direction of maximum gust.

Wind Speed (FG) in units of 0.1 m/s. Daily average FG plus measures for speeds at different times and parts of the day.

Wind Gust (FX) in units of 0.1m/s.  Daily average FX (24 hourly gusts) plus measures for maximums of different durations. (2 to 15 minutes).

Precipitation Amount (RR) in units of 0.1 mm. Daily total RR plus measures of amounts for intervals during the day.

Maximum Hourly Precipitation (MXR) in units of 0.1 mm. MXR for the day plus measures of amounts for intervals during the day.

Snow Depth (SD) in units of 1 cm. Mean daily SD plus measures of depths for intervals during the day.

Mean Temperature (TG) in units of 0.1C. Daily TG plus measures of various ways of calculating TG.

Minimum Temperature (TN) in units of 0.1C. Daily TN plus measures for different times and parts of the day.

Maximum Temperature (TX) in units of 0.1C. Daily TX plus measures for different times and parts of the day.

What is “Climate”?

To sort out the confusion between “weather” and “climate”, we can also look at how climate is measured and thereby defined. From the same ECA&D source is a climate indices database which is termed Indices of Extremes.

There is one datafile for each index. Each datafile gives information for all available stations in the ECA&D database. The indices are aggregated over the year, the winter-half (ONDJFM), the summer-half (AMJJAS), winter (DJF), spring (MAM), summer (JJA), autumn (SON) and each of the calendar months.

There are 74 indices grouped into twelve categories corresponding with different aspects of climate change. Some categories come directly from weather elements, while others are derivations.

The 74 indices are statistics built upon weather data, adding patterns of interest to humans. For example, temperature is greatly emphasized by adding various concerns with heat and cold on top of temperature records. Also, a compound category focuses on temperature and precipitation combinations and their favorability to humans.

What is Climate: Categories and Indices

Note that climate is operationally defined as statistical patterns of weather data. Some indices are simply averages of daily weather over long term periods. By convention, a 30-year average is used to define a climate baseline for a location.

Other climate indices are based on value judgments according to human interests. For example, heat and cold include many examples like growing days, good tourism days, heating degree days. In fact, a feature of climate is the imposition of human expectations upon nature, other examples being the sunshine indices Mostly Sunny and Mostly Cloudy days.

Andrew John Herbertson, a British geographer and Professor at Oxford, wrote in a textbook from 1901:

By climate we mean the average weather as ascertained by many years’ observations. Climate also takes into account the extreme weather experienced during that period. Climate is what on an average we may expect, weather is what we actually get.

Mark Twain, who is often credited with that last sentence, actually said:

Climate lasts all the time and weather only a few days.

The point is, weather consists of events occurring in real time, while climate is a statistical artifact. Weather is like a baseball player swinging in the batter’s box, climate is his batting average, RBIs, bases on balls, etc.

What is “Climate Change”?

The usefulness of climate indices is suggested by the last category called compound, where temperature and precipitation patterns are combined. In fact those two factors are sufficient to define distinctive local climate zones..

Based on empirical observations, Köppen (1900) established a climate classification system which uses monthly temperature and precipitation to define boundaries of different climate types around the world. Since its inception, this system has been further developed (e.g. Köppen and Geiger, 1930; Stern et al., 2000) and widely used by geographers and climatologists around the world.

As an example, consider how the island of Hawaii looks with its climate zones indicated:

Note: This image comes from an interactive tool and uses a different color scheme than the global map above.  The table below shows the thresholds by which zones are defined.

Zones	Zones Description	Thresholds
A	Tropical climates	Tmin ≥ +18 °C
Af	Tropical rain forest	Pmin ≥ 60 mm
Am	Tropical monsoon	Pann ≥ 25(100 – Pmin) mm
As	Tropical savannah with dry summer	Pmin < 60 mm in summer
Aw	Tropical savannah with dry winter	Pmin < 60 mm in winter
B	Dry climates	Pann < 10 Pth
BW	Desert (arid)	Pann ≤ 5 Pth
BS	Steppe (semi-arid)	Pann > 5 Pth
C	Mild temperate	-3 °C < Tmin < +18 °C
Cs	Mild temperate with dry summer	Psmin < Pwmin, Pwmax > 3 Psmin, Psmin < 40 mm
Cw	Mild temperate with dry winter	Psmax > 10 Pwmin, Pwmin < Psmin
Cf	Mild temperate, fully humid	Not Cs or Cw
D	Snow	Tmin ≤ -3 °C
Ds	Snow with dry summer	Psmin < Pwmin, Pwmax > 3 Psmin, Psmin < 40 mm
Dw	Snow with dry winter	Psmax > 10 Pwmin, Pwmin < Psmin
Df	Snow, fully humid	Not Ds or Dw
E	Polar	Tmax < +10 °C
ET	Tundra	Tmax ≥ 0 °C
EF	Frost	Tmax < 0 °C

Köppen and Climate Change

The focus is on differentiating vegetation regimes, which result primarily from variations in temperature and precipitation over the seasons of the year. Now we have an interesting study that considers shifts in Köppen climate zones over time in order to identify changes in climate as practical and local/regional realities.  The paper is: Using the Köppen classification to quantify climate variation and change: An example for 1901–2010 By Deliang Chen and Hans Weiteng Chen Department of Earth Sciences, University of Gothenburg, Sweden

Hans Chen has built an excellent interactive website (here): The purpose of this website is to share information about the Köppen climate classification, and provide data and high-resolution figures from the paper Chen and Chen, 2013:  For more details on Chen and Chen see the post: Data vs. Models 4: Climates Changing

Summary:  Climate Change Defined

Chen and Chen provide a data-based definition of “climate change”. Climate zones are defined by past temperature and precipitation ranges observed by humans. The weather datasets and climate indices inform us whether or not the patterns in a place are moving outside the norm for that location. Climate change appears as a shift in zonal boundaries so that one place starts to resemble a neighboring zone with a different classification.  The table above shows the defined zones and thresholds.

The Chen and Chen analysis shows that almost half of climates around the world will get a year of weather outside of their normal ranges. Getting a decade of abnormal weather is much rarer. True climate change would be a shift enduring over a 30 year period which has been observed in less than 10% of all climate zones.

Summary: The Myth of “Global” Climate Change

Climate is a term to describe a local or regional pattern of weather. There is a widely accepted system of classifying climates, based largely on distinctive seasonal variations in temperature and precipitation. Depending on how precisely you apply the criteria, there can be from 6 to 13 distinct zones just in South Africa, or 8 to 11 zones only in Hawaii.

Each climate over time experiences shifts toward warming or cooling, and wetter or drier periods. One example: Fully a third of US stations showed cooling since 1950 while the others warmed. It is nonsense to average all of that and call it “Global Warming” because the net is slightly positive. Only in the fevered imaginations of CO2 activists do all of these diverse places move together in a single march toward global warming.

For more on measurements and science see Data, Facts and Information

Footnote:

This post was focused on the distinction between weather and climate, so extreme weather events were not discussed, since by definition such events are weather. Still the quote at the beginning shows that activists are working hard to attribute attention-grabbing events as proof of global warming/climate change.

Mike Hulme wrote a series of articles describing the unsuccessful effort to link extreme weather to climate change and said this:
In recent decades the meaning of climate change in popular western discourse has changed from being a descriptive index of a change in climate (as in ‘evidence that a climatic change has occurred’) to becoming an independent causative agent (as in ‘climate change caused this event to happen’). Rather than being a descriptive outcome of a chain of causal events affecting how weather is generated, climate change has been granted power to change worlds: political and social worlds as much as physical and ecological ones.

More at X-Weathermen are Back 

 

h/t tom0mason for inspiring this post, including his comment below

The Pendulum is Settled Science

I attended North Phoenix High School (Go Mustangs!) where students took their required physics class from a wild and crazy guy. Decades later alumni who don’t remember his name still reminisce about “the crazy science teacher with the bowling ball.”

To demonstrate the law of conservation of energy, he required each and every student to stand on a ladder in one corner of the classroom. Attached to a hook in the center of the rather high ceiling was a rope with a bowling ball on the other end. The student held the ball to his/her nose and then released it, being careful to hold still afterwards.

The 16 pound ball traveled majestically diagonally across the room and equally impressively returned along the same path. The proof of concept was established when the ball stopped before hitting your nose (though not by much).  In those days we learned to trust science and didn’t need to go out marching to signal some abstract virtue.

The equations for pendulums are centuries old and can predict the position of the ball at any point in time based on the mass of the object, length of the rope and starting position.

Pictured above is the currently operating Foucault pendulum that exactly follows these equations. While it had long been known that the Earth rotates, the introduction of the Foucault pendulum in 1851 was the first simple proof of the rotation in an easy-to-see experiment. Today, Foucault pendulums are popular displays in science museums and universities.

What About the Double Pendulum?

Just today a comment by tom0mason at alerted me to the science demonstrated by the double compound pendulum, that is, a second pendulum attached to the ball of the first one. It consists entirely of two simple objects functioning as pendulums, only now each is influenced by the behavior of the other.

Lo and behold, you observe that a double pendulum in motion produces chaotic behavior. In a remarkable achievement, complex equations have been developed that can and do predict the positions of the two balls over time, so in fact the movements are not truly chaotic, but with considerable effort can be determined. The equations and descriptions are at Wikipedia Double Pendulum

But here is the kicker, as described in tomomason’s comment:

If you arrive to observe the double pendulum at an arbitrary time after the motion has started from an unknown condition (unknown height, initial force, etc) you will be very taxed mathematically to predict where in space the pendulum will move to next, on a second to second basis. Indeed it would take considerable time and many iterative calculations (preferably on a super-computer) to be able to perform this feat. And all this on a very basic system of known elementary mechanics.

And What about the Climate?

This is a simple example of chaotic motion and its unpredictability. How predictable is our climate with so many variables and feedbacks, some known some unknown? Consider that this planet’s weather/climate system is chaotic in nature with many thousands (millions?) of loosely coupled variables and dependencies, and many of these variables have very complex feedback features within them.

Summary

To quote the IPCC:

The climate system is a coupled non-linear chaotic system, and therefore the long-term prediction of future climate states is not possible. Rather the focus must be upon the prediction of the probability distribution of the system’s future possible states by the generation of ensembles of model solutions.

A recent National Review article draws the implications:
The range of predicted future warming is enormous — apocalyptism is unwarranted.

But as the IPCC emphasizes, the range for future projections remains enormous. The central question is “climate sensitivity” — the amount of warming that accompanies a doubling of carbon dioxide in the atmosphere. As of its Fifth Assessment Report in 2013, the IPCC could estimate only that this sensitivity is somewhere between 1.5 and 4.5°C. Nor is science narrowing that range. The 2013 assessment actually widened it on the low end, from a 2.0–4.5°C range in the prior assessment. And remember, for any specific level of warming, forecasts vary widely on the subsequent environmental and economic implications.

For now, though, navigating the climate debate will require translating the phrase “climate denier” to mean “anyone unsympathetic to the most aggressive activists’ claims.” This apparently includes anyone who acknowledges meaningful uncertainty in climate models, adopts a less-than-catastrophic outlook about the consequences of future warming, or opposes any facet of the activist policy agenda. The activists will be identifiable as the small group continuing to shout “Denier!” The “deniers” will be identifiable as everyone else.

Update May 2

Esteemed climate scientist Richard Lindzen ends a very fine recent presentation (here) with this description of the climate system:

I haven’t spent much time on the details of the science, but there is one thing that should spark skepticism in any intelligent reader. The system we are looking at consists in two turbulent fluids interacting with each other. They are on a rotating planet that is differentially heated by the sun. A vital constituent of the atmospheric component is water in the liquid, solid and vapor phases, and the changes in phase have vast energetic ramifications. The energy budget of this system involves the absorption and reemission of about 200 watts per square meter. Doubling CO2 involves a 2% perturbation to this budget. So do minor changes in clouds and other features, and such changes are common. In this complex multifactor system, what is the likelihood of the climate (which, itself, consists in many variables and not just globally averaged temperature anomaly) is controlled by this 2% perturbation in a single variable? Believing this is pretty close to believing in magic. Instead, you are told that it is believing in ‘science.’ Such a claim should be a tip-off that something is amiss. After all, science is a mode of inquiry rather than a belief structure.

Here is a fine exposition of Bob Carter’s thoughts on the field of climate science and why we should not jump to conclusions concerning global warming/climate change.  The text and some illustrations are provided by Russ Swan in his post (here).  I added one at the end.

Have you ever wondered about these people when they are so definite about mankind causing climate change? Have you ever wondered how much of the information is from their own expertise and how much is what they’ve learned from someone else? Are they really passing on real proven scientific facts or just what they believe to be true from information provided by someone else?

Or do you just accept what they are telling you?

The average person on the street might be forgiven for thinking that climate change scientists are primarily meteorologists or climatologists plus perhaps some others with supporting expertise.  But that would be only partially right.

The subjects relating to climate change actually diverge into more than 100 scientific sub-disciplines, the elements of which can be exceptionally intricate, highly complicated and intertwined.  Just changing one of the many data inputs e.g. the output chemistry of sub-sea volcanoes to a climate change puzzle can flow-on to incorrect or at least misleading changes in the final solution. And the answer will still be a “best probable” result – not fact.

At most there may be a handful of scientists that have mastery of two or three scientific disciplines such as Professor Robert M. Carter (decd) who was a qualified palaeontogist, stratigrapher and marine geologist.  Yet even if a scientist does have expertise in two or more of the climate change elements, he/she still needs to find and use data from other sources to cover the gaps in his/her own knowledge. Such data may in turn only be a “best probable” solution as opposed to fact(s) as will be explained further below.

No Such Thing as a Climate Expert

It must therefore be obvious that there can be no such thing as an “expert” simply because no one can fully comprehend the entirety of it all.

This doesn’t stop the media, in particular the TV media in regularly presenting interviewees as experts to lend credibility to their show. But anyone who claims or admits to being an expert in climate change is either kidding themselves, egocentric or is being deceitful.

The bottom line is that when a supposed expert fronts up in the media – watch it guardedly or else switch the channel.   At the end of the day everyone, including the scientists themselves are basically amateurs when a topic is outside their own field of expertise – even if they are an educated amateur.

But having someone with at least some scientific background involved in climate change discussions has got to be far more preferable than pulling celebrities into the debate. These people despite their best intentions, are simply promoting their own views and muddying the waters for the public to make a realistic conclusion in their own minds.

Conclusion

Apart from that all three groups of scientists generally DO agree that the Earth’s climate has always changed, that human emissions affect local climates e.g. urban areas and have a summed potential to affect climate globally, and that carbon dioxide is a mild greenhouse house – note the word “mild”.

The real argument then is not about whether the Earth is heating up, but about how relevant is AGW when considered against natural climate change processes.

The Blind Men and the Elephant (Indian Fable)

Footnote:  For more on science as knowledge rather than opinion see Yellow Climate Journalism

 

 

A previous post on Temperature Misunderstandings addressed mistaken notions about the meaning of temperature measurements and records. This post looks at rainfall, the other primary determinant of climates. For this topic California provides the means for everyone to see how misconceptions arise, and how to see precipitation statistics in context.

Lessons learned from the end of California’s “permanent drought”

A report by Larry Kummer documents how extensively California’s recent shortage of water was proclaimed as a “permanent drought”. And it goes on to document how El Nino conditions have ended the water shortage.

Status of the California drought

“During the past week, a series of storms bringing widespread rain and snow showers impacted the states along the Pacific Coast and northern Rockies. In California, the cumulative effect of several months of abundant precipitation has significantly improved drought conditions across the state.”
— US Drought monitor – California, February 9.

Precipitation over California in the water year so far (October 1 to January 31) is 178% of average for this date. The snowpack is 179% of average, as of Feb 8. Our reservoirs are at 125% of average capacity. See the bottom line summary as of February 7, from the US Drought monitor for California.

The improvement has been tremendous. The area with exceptional drought conditions have gone year over year from 38% of California to 0%, extreme drought from 23% to 1%, severe drought from 20% to 10% — while dry and moderate drought went from 18% to 48%, and no drought from <1% to 41%. See the map below. And the rain continues to fall.

In addition there is the saga of Oroville dam threatened by its reservoir overfilling.

Confusing Weather and Climate

As with temperature, rainy weather is not climate. Neither is fair, sunny weather permanent. Precipitation is variable in any particular climate, with the seasons and on decadal and mult-decadal bases. For a context on precipitation patterns around the world see Here Comes the Rain Again.

It is a mistake to call a temporary lack of rain a drought, or worse a permanent drought, and equally a mistake to call a return of rainfall the end of a drought. California’s history as a desert environment does not change just because politicians and the public have short memories.

H/T to Eric Simpson for reminding us of that history:

There is also this perceptive comment by tomholsinger

I wouldn’t be so quick about the drought ending. Droughts are ALWAYS multi-season events. I was very impressed by the references below, which made the point that the 20th Century average of ~200 million acre feet of precipitation in California (rain and snow combined) is way more than the average of ~140 million acre feet over the last 2000 years.

Drying of the West, National Geographic

The West without Water: What Past Floods, Droughts, and Other Climatic Clues Tell Us about Tomorrow, Ingram, B. Lynn, and Malamud-Roam, Frances, 2013, University of California Press

Tom goes on to quote himself from a Modesto Bee op-ed almost two years ago.

Global warming has nothing to do with this – history is bad enough. A long-standing pre-industrial regional climate fluctuation seems underway, returning us from the wettest century in the past 1000 years to at least the historic average of much less (~70%) rain and snow. Many paleoclimatologists believe we are entering a still worse mega-drought .

An extreme drought by historic standards means a drop to 35-40% of the 20th Century average for 10-20 years. California has experienced two centuries-long such extreme mega-droughts in the past 2000 years.

Our average 20th Century precipitation (rain and snow combined) produced about 200 million acre feet of water annually over the whole state. 118 million acre feet went to nature in 2000, and 82 million was allocated by humans – the first 39 million for federal mandates, 9 million was used by people and industry, and the last 34 million for irrigation. A drop to the historic average of ~140 million acre feet over the past 2000 years means extinction for California agriculture – it would bear almost all the burden of the decrease even if the federal water is released. An extreme drought means a drop to about 75 million acre feet, and we might be starting 1-2 centuries of that.

This is happening to the entire Southwest . ~20 million acre feet of the Southwest’s precipitation annually entered the Colorado River in the 20th Century, of which ~12 million is currently withdrawn by Americans. Colorado River flow too has averaged much less over the past 2000 years (12-14 million acre fee annually), and it drops to 7-8 million in droughts which sometimes last centuries.

A drop to only the historic average precipitation over the past 2000 years means catastrophe for the Southwest. 2/3 of the very wet 20th Century average is normal for the entire area. We can expect ALL of California’s allotment of Colorado River to be diverted to urban areas in Arizona and Nevada in the decades of drought the region seems to be entering.

Summary

As with temperatures, changes in precipitation are misinterpreted when taken out of historical context. This is usually done to hype a sociopolitical agenda by distracting people from the baseline realities to which we can only adapt, not prevent.

The rainfall measures above show that California enjoyed an unusually wet century and it would have been prudent to take advantage of it by storing water resources. As the fable tells us, grasshoppers live for today, ants prepare for tomorrow.