Written by Dr Peter J. Carson (PhD in Physical Chemist)
Australian Physical Chemist uses standard science to test whether ‘greenhouse gases’ – key to the theory behind man-made global warming – really can have any greenhouse effect on other planets.
Dr Peter J Carson (University of Adelaide) shows that careful comparison of the different concentrations of atmospheric carbon dioxide (CO2) on Earth, Venus and Mars determines that any supposed ‘greenhouse gas effect’ has no relation to the amount of atmospheric CO2.
Dr Carson’s analysis, set out below and linked here, is a compelling debunk of the claims that adding more CO2 into the atmosphere will alter the temperature of a planet’s surface. In effect, Carson shows that the theory of anthropogenic global warming (AGW) is false.
To encourage belief in the man-made global warming narrative pseudo scientists require that the ignorant and uninformed among us first buy into their lie than outer space is cold. Why? Because if we buy into ‘cold outer space’ then we are nicely set up to be duped by the nonsense that earth’s atmosphere ‘keeps us warmer than we would otherwise be.’
The narrative of these pseudo scientists is that ‘greenhouse gases’ are ‘trapping’ heat and/or ‘delaying cooling of our atmosphere otherwise, if they didn’t, we would all freeze our butts off because ‘cold’ outer space is ‘freezing.’ And all those nasty ‘carbon emissions’ we pump out living our industrialized western lives adds more ‘greenhouse gas heating’ to the mix. (All utter BS)
Europe and the US have been building onshore wind turbine plants in rural areas for more than 25 years. Anyone living within about 1.0 mile of such plants would hear the noises year-round, year after year. Those nearby people would be experiencing:
Decreasing property values.
Damage to their health, due to lack of sleep and peace of mind.
Living with closed windows and doors, due to year-round noises.
Exposure to infrasound.
The wind turbine noise problem is worldwide. Due to a lack of worldwide guidelines, various political entities have been developing their own codes for the past 30 years. The World Health Organization is finally addressing the lack of detailed guidelines regarding such noises.
World Health Organization Noise Guidelines: WHO, publishes detailed guidelines regarding various, everyday noises, such as near highways and airports, within urban communities and in work places. The guidelines serve as input to local noise codes.
In general, wind turbines are located in rural areas. When they had low rated outputs, say about 500 kW in the 1960s and 1970s, they made little audible noise, and the infrasound was weak. However, when rated outputs increased to 1000 kW or greater, the audible and infrasound noises became excessive and complaints were made by nearby people all over the world.
Worldwide guidelines regarding wind turbine noises are needed to protect nearby rural people, such as regarding:
The maximum outdoor dBA value, how that value is arrived at, such as by averaging over one hour, where that value is measured, such as near a residence, or at the resident property line to enable that resident to continue to enjoy his entire property.
How to measure, or calculate the outdoor-to-indoor sound attenuation of a residence.
How much setback is needed, such as one mile to minimize infrasound impacts on nearby residents.
The maximum dB value of infrasound, how that value is arrived at, where that value is measured.
How to determine the need for a 5 dB annoyance penalty.
The lack of such guidelines has resulted in various political jurisdictions creating their own codes. That process has been heavily influenced by well-financed, pro-wind interests, which aim to have the least possible regulation to maximize profits.
Comparison of Wind Turbine Codes: Below are some highlights from the noise codes of various political entities to illustrate their diversity:
1) DENMARK: Because Denmark was an early developer of wind turbine plants, its noise code is more detailed than of most political entities. It has a buffer zone of 4 times total height of a wind turbine, about 4 x 500 = 2,000 ft, about 0.61 km (no exceptions), and it also has the following requirements regarding outdoor and indoor noise:
OUTDOOR
For dwellings, summer cottages, etc.: 39 dBA (wind speeds of 8 m/s, 18 mph) and 37 dBA (wind speeds of 6 m/s, 13 mph)
For dwellings in open country: 44 dBA (wind speeds of 8 m/s) and 42 dBA (wind speeds of 6 m/s)
The belowregulations describe the methods and time periods over which sounds are to be measured:
Page 4, par 5.1.1 mentions averaging over various periods. Only the worst average readings of a period are to be considered for compliance.
Page 4, par 5.1.2 mentions a 5 dB annoyance penalty must be added to the worst average readings for a period for clearly audible tonal and impulse sounds with frequencies greater than 160 Hz, which would apply to wind turbine sounds.
Page 6, par 5.4 mentions limits for indoor A-weighted low frequency noise 10 – 160 Hz, and G-weighted infrasound 5 – 20 Hz.
“If the perceived noise contains either clearly audible tones, or clearly audible impulses, a 5 dB annoyance penalty shall be added to the measured equivalent sound pressure level” That means, if a measured outdoor reading is 40 dBA (open country, wind speed 6 m/s), and annoyance is present, the reading is increased to 45 dBA, which would not be in compliance with the above-required 42 dBA limit.
In some cases, a proposed wind turbine plant would not be approved, because of the 5 dB annoyance penalties. The noise of wind turbines varies up and down. The annoyance conditions associated with wind turbines occur year-round. The annoyance conditions associated with other noise sources usually occur much less frequently.
NOTE: The 5 dB penalty does not apply to indoor and outdoor low frequency and infrasound noises, i.e., 160 Hz or less.
INDOOR
– For both categories (dwellings, summer cottages, etc.; open country), the mandatory limit for low frequency noise is 20 dBA (Vermont’s limit is 30 dBA), which applies to the calculated indoor noise level in the 1/3-octave bands 10 – 160 Hz, at both 6 and 8 m/s wind speed. The purpose of the regulation is to ensure neither the usual noise, nor the low frequency noise, will annoy nearby people when the wind turbines are in operation.
Denmark’s Controversial Noise Attenuation Calculations: The controversy in Denmark is regarding the Danish EPA assuming high attenuation factors for calculating attenuation from 44 dBA (outdoor) to 20 dBA (indoor, windows closed) for frequencies above 63 Hz, which yield calculated indoor noise levels less than 20 dBA. The Danish EPA prefers assuming high factors, because they result in compliance, which is favorable for wind turbines.
However, acousticsengineers have made indoor field measurements (supposedly “too difficult to measure”, according to the Danish EPA), which indicate many houses near wind turbine plants have lower than assumed attenuation factors, which results in indoor noise levels greater than 20 dBA, i.e., non-compliance, which is not favorable for wind turbines.
However, the final arbiters should not be government personnel using assumptions, but the nearby people. Increasingly, those people are venting their frustrations at public hearings and in public demonstrations.
2) POLAND is considering a proposed a law with a 2.0 km (1.24 mile) buffer zone between a wind turbine and any building. That means at least 65% of Poland would be off limits to wind turbines. Future wind turbine plants likely would be offshore.
3) BAVARIA, a state in Germany, just enacted a setback of 10 times turbine height, i.e., 10 x 500 ft = 5,000 ft, almost one mile. In Germany, the wind turbine nighttime noise limit is not to exceed 35 dBA.
The second URL shows what happens when it is sunny and windy in Germany. The excess energy is dumped onto connected grids at near-zero wholesale prices. This has been happening more and more hours of the year.
4) LETCHER TOWNSHIP, South Dakota, voted for a 1-mile buffer zone. Under the approved ordinance, no large wind turbine plant could be built within 5,280 feet of the nearest residence of a non-participating homeowner, or within 1,500 feet of the nearest neighbor’s property line.
5) NEW HAMPSHIRE’s wind turbine code requires the following:
Sound: Wind turbine plants must meet a ‘not-to-exceed’ standard of 45 dBA from 8am – 8pm and 40 dBA from 8pm – 8am. The sound measurements are to be taken ‘on property that is used in whole or in part for permanent or temporary residential purposes.’
Shadow Flicker: A shadow-flicker assessment must be completed for each residence, learning space, workplace, health care setting, public gathering place (outdoor and indoor), other occupied building and roadway, within a minimum of 1 mile of any turbine, based on shadow flicker modeling that assumes an impact distance of at least 1 mile from each of the turbines. Shadow flicker may not occur more than 8 hours per year at any of these locations.
Setbacks: The applicant must complete an assessment of the risks of ice throw, blade shear, tower collapse on any property, roadway, etc. A committee will determine, on a case-by-case basis, whether there is a concern with the setbacks and/or the appropriate distance that should be set.
6) MAINE’s wind turbine noise code requires the following:
In 2012, the Maine Board of Environmental Protection adopted noise control regulations that are specific to wind turbine plants.
Maine DEP Chapter 375.10(I) of Maine DEP regulations specifies sound level limits for wind turbine plants as 55 dBA from 7am – 7pm (the “daytime limit”), and 42 dBA from 7pm – 7am (the “nighttime limit”) averaged over one hour, at protected locations.
Maine DEP nighttime limits apply as follows:
Within 500 feet of a residence on a protected location or at the (project) property line, if closer to the dwelling. The resulting sound levels at a residence itself are usually lower than at 500 feet from the dwelling or at the property line where the 42 dBA “nighttime limit” applies.
Beyond 500 feet, the daytime limit of 55 dBA applies 24 hours per day.
Maine DEP Chapter 375.10 noise rules establish sound level limits on an hourly basis although compliance for wind turbine plants is evaluated by averaging sound levels over twelve or more ten-minute measurement intervals with turbines operating at full-rated sound output. There are also special provisions and “penalties” that apply when the sound generated by a wind project result in tonal or short-duration, repetitive sounds. This standard is described in more detail in the remainder of this report. See URL.
Maine DEP Chapter 375.10, Section I, requires a 5 dB annoyance penalty be added for certain occurrences of tonal and short duration repetitive (SDR) sounds when determining compliance with hourly sound level limits.
7) VERMONT has an ad hoc wind turbine code , i.e., applied on a project-by-project basis.
The code allows a maximum noise of 45 dBA (outdoor), averaged over one hour, as measured at a nearby residence. The averaging makes disappear random noise spikes of 60 – 70 dBA, which disturb the sleep of nearby people.
The code allows a maximum noise of 30 dBA (indoor, windows closed), averaged over one hour.
The code makes no distinction for daytime and nighttime, even though people may want to have open windows, especially during warm nights.
Vermont’s code has: 1) no required buffer zone; 2) no required infrasound limit; 3) no 5 dB annoyance penalty; 4) the indoor limit is 30 dB, whereas the Denmark limit is 20 dB.
In Vermont, residences cannot attenuate 45 dBA (outdoor) to 30 dBA (indoor, windows closed), according to acoustics tests. See URL.
NOTE: If Denmark’s residences cannot attenuate 44 dBA (outdoor) to 20 dBA (indoor, windows closed), and Vermont residences cannot attenuate 45 dBA to 30 dBA (a much easier requirement), then the options are: 1) have lesser capacity wind turbines; 2) locate them further away from residences, i.e., a greater buffer zone; 3) upgrade the attenuation of nearby residences; 4) buy out the owners.
The Vermont code is much less strict than of Denmark and New Hampshire, largely because of the political influence of RE special interests. Five years ago, the Vermont Public Service Board could have copied major parts of the Danish code to create a Vermont code that actually protects nearby people.
Measuring Wind Turbine Sounds: This article describes in detail some aspects of measuring wind turbine sounds.
Everyday noises in the audible range are weighted using a curve that approximates the response of the human ear. See figures 1 and 2 of article. If the A-curve is applied to sound measurement dB readings, they are designated as dBA.
The dB levels of frequencies below about 200 cycles per second, i.e., 200 Hz, are artificially lowered, due to the A-curve application. That includes infrasound frequencies of 20 Hz, or less. See figure 3 of article.
The site background noise is affected by wind speed. At near zero wind speed, as often occurs in rural areas at night, the noise is about 10 to 15 dBA. See figure 4 of article.
Outdoor-to-indoor attenuation of infrasound below 4 Hz is near zero for a wood-frame house 1,300 meters (4,265 ft) from a wind turbine. See figure 8 and 9 of article. Whereas a resident would not hear such noises, they would create significant physical discomfort, such as nausea, headaches, dizziness, etc., if the noises were strong, i.e., have high dB values.
Figure 11 of the article shows a similar lack of outdoor-to-indoor attenuation of infrasound for a house 8,000 meters from a wind turbine. The conclusion is: Infrasound below 4 Hz travels long distances and is very little attenuated by a wood-frame house.
Infrasound: Sounds with frequencies of 20 Hz, or less, are defined as infrasound. Those sounds are not heard, but felt. A rotor blade passing the mast of a wind turbine creates a burst of audible and inaudible sound of various frequencies. The base frequency is about one cycle per second, similar to a person’s heart beat, and the harmonics, at 2, 4 and 8 Hz, are similar to the natural frequencies of other human organs, i.e., ears, eyes, liver, kidneys, etc., which start vibrating.
The natural frequencies of wood-frame house walls are less than 20 Hz. The infrasound induces them to start vibrating, which creates standing, inaudible air pressure waves inside the rooms of a house. As a result, nearby people find life inside their houses unbearable. Often they abandon their houses, or sell at very low prices.
Infrasound interferes with the body’s natural biorhythms, and causes adverse health impacts on nearby people and animals, including DNA damage to nearby pregnant women and animals, their fetuses, and newborn offspring. See URLs.
Infrasound travels long distances. A buffer zone of about 1 mile is required to reduce adverse impacts on people. However, roaming animals would continue to be exposed.
Acoustics consultants usually deal with OSHA-type measurements of everyday noises. Most of them have almost no experience measuring infrasound, which requires special instrumentation and test set-ups. As a result, acoustics consultants take the easy way out by claiming infrasound does not exist. That measurements of low frequency noise are made to look less on an A-weighted basis helps their argument.
If acoustics consultants admit infrasound does exist, they provide a list of studies proving it does no harm. To which opponents reply with a list of studies that state it does harm to nearby people.
Some governments have used infrasound as a non-lethal weapon for torture or crowd control. It leaves no marks.
The Need for a 5 dB Annoyance Penalty: Rural nighttime ambient noise is 20 – 40 dBA, and urban residential nighttime ambient noise is 58 – 62 dBA. In many rural areas, nighttime outdoor ambient noise averages about 20 dBA.
People who live in urban areas have no idea how quiet it is in rural areas. For example: the introduction of clusters of 3 MW wind turbines, on 2,000-ft ridgelines in New England, came as a total shock to nearby rural people. Being high up, the noise carries far, especially the infrasound.
The dB values to indicate noises are a proxy for sound pressure level, SPL. The ears of people are sensitive to sound pressure. The below table clearly indicates random noise spikes above 50 dB have high SPL values, which are highly disturbing to nearby people, especially at night. Any wind turbine noise guidelines and codes must be based on rural noise values.
A 45 dB noise has an SPL 5.6 times greater than a 30 dB noise; 17.8 times greater than a 20 dB noise.
A 63 dB random spike has an SPL 44.9 times greater than a 30 dB noise; 142 times greater than a 20 dB noise.
Noise level
Noise, dB
Times reference pressure*
Rural average outdoor
20
10.0
Rural average outdoor
30
31.6
Rural average outdoor near a residence
45
177.8
Rural random spike
51
354.8
Rural random spike
57
709.6
Rural random spike
63
1419.2
Rural random spike
69
2838.4
* The commonly used reference sound pressure in air is 20 micro-pascal. It is considered the threshold of human hearing (roughly the sound of a mosquito flying 3 m away).
General Comments: As almost all recently installed wind turbines are rated at 2 – 3 MW, and as almost all such units are in rural settings, government noise codes should use the rural nighttime ambient noise level as the basis for limiting wind turbine noises.
Ever-present, random spike noises, with higher dB values, say 60 – 70 dBA, can occur, during an hour, but the “averaging over one hour” makes these noises disappear; hence the reason for Denmark, Maine, etc., having a 5 dB annoyance penalty.
These peak noises are most annoying, they occur at random, and mostly at night. They adversely affect the health of nearby people. As a minimum, they deprive nearby people from getting a good night’s sleep to recover from the prior day, and to get ready for the next day. According to WHO, restful sleep is a basic requirement for good mental and physical health, as are food, water, air, etc.
Denmark holds infrasound is harmful to the health of nearby people and animals. Therefore, it has an infrasound requirement in its wind turbine code. Here is a chart and 4 articles prepared by Rand and Ambrose, two prominent acoustics engineers, which shows Vermont’s noise limit.
In my recent article “The Climate Religion”, I argued that “climate change”, the widespread belief that atmospheric CO2 controls climate and climate events, satisfies the defining criteria of a state religion. Professor Paul Brown responded to my article in his article entitled “The Religion of Climate Change Denial”. This is my reply to Professor Brown.
Professor Brown is silent on my argument that climate change science and policy serve global financiers and US-dominated geopolitics. He prefers a sanitized argument essentially limited to a pronouncement that “most scientists…”. Fine, let us examine the scientific question.
An elementary rule of scientific theorizing, which all (100{154653b9ea5f83bbbf00f55de12e21cba2da5b4b158a426ee0e27ae0c1b44117}) of scientists admit, is that one cannot prove a theory. One can only disprove a theory. Therefore, it is scientific to “deny”, and it is unscientific to assert validity of a theory on the basis that most scientists do not expressly oppose the said theory.
Hey fellers, I must have given the wrong impression. One of my critics on Facebook, one of those who are forever trying to trash my articles, has pointed to the temperatures on the Moon, which to all intents and purposes has no atmosphere. He made a very important point. I cannot find his article right now, but it is clear that Moon temperatures vary between +200ºC and –200ºC.
I guess that those are very convenient numbers as the average Lunar Mean Temperature must be zero! I only put this in, in order to demonstrate just how useless is our own Global Mean Temperature. An average simply does not show the extremes, and it is the extremes that matter. Say you were in the Sahara, dying of thirst and heat, would you be happy to know that the Global Mean temperature is 14ºC? (I have just looked it up.) Or if you were in Mongolia, where the temperatures have dropped well below zero C. and you were literally freezing to death, what comfort would the knowledge of a Global Mean Average be to you?
Climate scientists performing analysis of Scots pine trees over an 810-year period for a summer temperature reconstruction discover that temperatures were warmer in the periods around 1300s, 1500s, and 1730s.
Abstract: This study presents a summer temperature reconstruction using Scots pine tree-ring chronologies for Scotland allowing the placement of current regional temperature changes in a longer-term context.
‘Living-tree’ chronologies were extended using ‘subfossil’ samples extracted from nearshore lake sediments resulting in a composite chronology >800 years in length. The North Cairngorms (NCAIRN) reconstruction was developed from a set of composite blue intensity high-pass and ring-width low-pass filtered chronologies with a range of detrending and disturbance correction procedures.
Definition of “Fake News”: When reporters state their own opinions instead of bearing witness to observed events.
We are now fully entrenched in an age of “yellow” journalism, especially regarding the issue of global warming/climate change. Below I will deconstruct a recent egregious example, but first we need a background from renowned philosopher Mortimer Adler.
“It is generally accepted that the climate warms during periods of strong solar activity (e.g., the Medieval Warm Period) and cools during periods of low solar activity (e.g., the Little Ice Age).” — Lyu et al., 2016
Scientists are increasingly tuning out the claims that the Earth’s temperatures are predominantly shaped by anthropogenic CO2 emissions, or that future climate is destined to be alarmingly warm primarily due to the rise in trace atmospheric gases. Instead, solar scientists are continuing to advance our understanding of solar activity and its effect on the Earth system, and their results are progressively suggestive of robust correlations between solar variability and climate changes.
For example, in 2016 alone, there were at least 132 peer-reviewed scientific papers documenting a significant solar influence on climate. Among them there were 18 papers that directly connected centennial-scale periods of low solar activity (the Little Ice Age) with cooler climates, and periods of high solar activity (the Medieval Warm Period and the Modern Warm Period [20th Century]) with high solar activity levels. Another 10 papers warned of an impending solar minimum and concomitant cooling period in the coming decades.
And this trend of scientists linking climate changes to solar forcing mechanisms — and bypassing an anthropogenic explanation — continues to rage on in 2017.
Written by Dr Peter J. Carson (PhD in Physical Chemistry)
Earth’s surface receives energy from the Sun, and its heating effect reduces with distance, described by the Stefan-Boltzmann relationship. At Earth’s distance from the Sun, the average temperature is reckoned to be about -18°C as calculated from Stefan-Boltzmann, whereas the actual average temperature is about 33°C higher than that.
A generally accepted assertion is that that 33°C difference is due to the Greenhouse Gas effect, ie the atmospheric gases that are able to absorb IR energy, known as “Greenhouse Gases”, are responsible for that 33°C difference. I haven’t seen any substantiation of that assertion. This article tests that assertion.
The name “Greenhouse Gas” (GG). It is recognised the name is not really appropriate for the heat captured in the atmosphere by such “Greenhouse” molecules as CO2 or H2O, but the name has certainly captured the attention!
If only we would all just use our rational, scientific minds. Then we could get past our disagreements. It’s a nice thought. Unfortunately, it’s wrong.
Yale behavioral economist Dan Kahan has spent the last decade studying whether the use of reason aggravates or reduces partisan beliefs. His research shows that aggravation easily wins. The more we use our faculties for scientific thought, the more likely we are to take a strong position that aligns with our political group. That goes for liberals as well as conservatives.
Rather than use our best thinking to reach the truth, we use it to find ways to agree with others in our communities.
In 1924, German biochemist Otto Warburg observed that cancer cells are extraordinarily greedy. Tumours tend to grow rapidly, so it made sense that they had outsized appetites. But Warburg also found that the way they burned, or metabolised, the resources they gobbled so hungrily was different. He was convinced that this change in metabolism defined cancer – and figuring out what drove it would let us beat the disease.
His idea caught on. For much of the 20th century, Warburg’s altered metabolism idea guided approaches to understanding and treating cancer. That all changed in the 1970s, with the discovery that certain gene mutations can cause cancer – and with it a sea change in how we might tackle the disease. Target the genes responsible, the new thinking went, and we could stop cancer in its tracks. Warburg’s ideas largely fell by the wayside.
Tear up that old textbook. A pyramid-shaped carbon molecule that contradicts one of the most basic chemistry lessons we learn at school has been studied for the first time. It contains a carbon atom that bonds to six other atoms instead of the four we have been told carbon is limited to.
Atoms form molecules by sharing electrons. Carbon has four electrons that it can share with other atoms. But in certain conditions, carbon can be stretched beyond this limit, says Moritz Malischewski, a chemist at the Free University of Berlin who synthesised and studied the molecule, called hexamethylbenzene.
U.S. wildlife releases a plan to protect polar bears from global warming, despite their numbers doubling over 50 years.
In what one zoologist is calling “fake news,” the US Fish & Wildlife Service (USFWS) announced the final version of a draft report that #Climate Change is the chief threat to polar bears. Released yesterday, the Conservation Management Plan (CMP) is a wide-ranging report to help save the Arctic polar bear as warmer temperatures eat away at their sea ice. And media outlets took the bait and ran misleading headlines using a recycled report from mid-2015.
These days, even shipwreck museums showcase evidence of climate change.
After diving recently among Key West’s fabled ship-destroying barrier reefs, I immersed myself in exhibits from the Nuestra Senora de Atocha, the fabled Spanish galleon that foundered during a ferocious hurricane in 1622. The Mel Fisher Maritime Museum now houses many of the gold, silver, emeralds and artifacts that Mel and Deo Fisher’s archeological team recovered after finding the wreck in 1985.
Also featured prominently in the museum is the wreck of a British slave ship, the Henrietta Marie. It sank in a hurricane off Key West in 1700, after leaving 190 Africans in Jamaica, to be sold as slaves.
Just beyond Earth’s home in the solar system, about 94 million miles from the Sun, a coal-black asteroid slowly rotates as it orbits our star. It’s about 1,650 feet across, with a slight bulge around the middle, like a spinning top. Its low density means it’s not solid, but instead it’s likely a crumbly pile of carbon-rich rocks held together by gravity.
The asteroid is called Bennu, and every six years, its egg-shaped orbital path brings it just 185,000 miles from Earth — roughly 53,000 miles closer than our moon. In about 200 years, there’s a 1-in-2,700 chance it could sail close enough for Earth’s gravity to reel it in. That would be very bad.
The impact would excavate a crater nearly three miles wide and 1,500 feet deep. Locations three miles away would be buried under 50 feet of rock raining down. It would trigger a 6.7-magnitude earthquake. But the real damage would come from the air burst, caused by the meteor hurtling through the atmosphere, which could collapse buildings and tear down trees up to 30 miles away.
The number one experiment quoted as proof of the greenhouse effect is Tyndall’s experiment. Specifically the absorption experiment described in his 1861 Bakerian lecture to the British Royal Society.[1]
In Tyndall’s experiment various gases are introduced into the gas observation chamber and it is noted that some gases (“greenhouse gases”) absorb more “calorific rays” (infrared) than others. This absorption is referred to as “proof of a greenhouse effect”.
It was the result of several months work on his part. But in fact Tyndall’s experiment shows nothing more than that EMR from a warmer object is absorbed by a colder one. Such absorption is not proof of a greenhouse effect.
