Sentences with phrase «uhi bias»

Following from your logic, if you haven't answered my other points on how UHI bias can be eliminated, can I take it you agree that the problem can be satisfactorily handled?

Every station should have reference stations added at the nearest pristine location near it, and the UHI bias measured and subtracted from the trend.

Even the UAH numbers will include UHI bias.

That, too, expands the effect of land temperature on the global estimate, including expanding the effect of any UHI bias.

I'd say the truth for UHI bias lies between Jones -LRB-.

There is accurate CO2 data but only since 1958 at Mauna Loa, as for temperature, well there are thousands of high quality rural weather stations throughout the world and especially in the US and the northern hemisphere that have long histories and NO UHI bias.

@John S: 1) The synthesized HADCRUT3 index, whose observational basis is very paltry prior to WWII and is corrupted by systematic UHI bias, is not a bona fide temperature time - series — let alone «climate» per se.

1) The synthesized HADCRUT3 index, whose observational basis is very paltry prior to WWII and is corrupted by systematic UHI bias, is not a bona fide temperature time - series — let alone «climate» per se.

And, the BEST temperature reconstruction still contains UHI bias.

The way to take UHI bias properly into account is to completely separate urban temp measurements from the rural measurements — problem solved.

``... since most people actually live in / on these UHI affected areas, perhaps a UHI bias needs to be taken into account?

That being said, since most people actually live in / on these UHI affected areas, perhaps a UHI bias needs to be taken into account??? If not, then I'll go with RSS!!!

The person playing a climatologist in the video claimed the UHI bias was a big factor in global warming.

It can also be demonstrated that the UHI biases the thermometers upwards.

Not exact matches

The question isn't whether UHI contributes to surface temperature rise, but whether it affect temperature measurements sufficiently to bias the measured averages.

[Response: You're missing the point, which is that the UHI is accepted, of course, but the point at issue is whether it affects temperature * trends *, which a constant bias doesn't.

See http://www.realclimate.org/index.php?p=43 for information about the UHI not causing the temperature record to be biased.

That means using meta - data, using corrections of known biases, comparing near - by stations, correcting for UHI etc..

So UHI provided a negative temperature bias?

The most likely explanation being that the land based thermometer record has become inaccurate due to station drop out, particularly high latitude drop out, a biasing towards airport stations, poor station siting and a failure to properly allow for UHI which is having an ever increasing impact upon post 1960s temperatures because of not simply an increase in urbanisation but also the drop out of rural stations and the ever increasing percentage of airport stations and airports have so greatly changed during the 1970s and 1980s.

The most likely explanation being that teh land based thermometer record has become inaccurate due to station drop out, particularly high latitude drop out, a biasing towards airport stations, poor station siting and a failure to properly allow for UHI which is having an ever increasing impact upon post 1960s temperatures because of not simply an increase in urbanisation but also the drop out of rural stations and the ever increasing percentage of airport stations and airports have so greatly changed during the 1970s and 1980s.

It shouldn't be surprising that the UHI effect is not a big source of error in the temperature trend, because a stable temperature bias because of bad siting will not affect the trend.

Lighthouses would appear to an excellent source of data free from UHI and other biases.

«[NASA is] supposed to make a «homogenisation adjustment,» to allow for [urban heat island (UHI)-RSB- bias,» Homewood wrote.

It strikes me as ridiculous that UHI can be claimed not to bias the temperature record upwards.

Related to sampling bias, skeptics argued that there was bias due to UHI.

It may be that UHI in and of itself is minor, or that the direct effects are only the bias upon the sampling, known or not, corrected or not.

They have said above (in their replies, but not in the paper itself) that that particular AGW signal is bounded by a maximum of.66 C per century, and that the AGW signal may come from (1) a recent CO2 increase — which you are apparently assuming is the sole source), (2) measurement error / bias (UHI and bad thermometer sites) and (3) other causes.

Also to be considered is whether the site is included within a region that is or becomes urban, in which case the UHI adjustments mentioned previously may cancel out any bias completely.

It shows that the CRU and NOAA failures to make UHI adjustments along the lines of GISS are introducing a substantial bias in these records.

As I am understanding it this bias exists as GISS is currently adjusting their data for UHI effects.

See, the first thing to do is do determine what the temperature trend during the recent thermometer period (1850 — 2011) actually is, and what patterns or trends represent «data» in those trends (what the earth's temperature / climate really was during this period), and what represents random «noise» (day - to - day, year - to - random changes in the «weather» that do NOT represent «climate change»), and what represents experimental error in the plots (UHI increases in the temperatures, thermometer loss and loss of USSR data, «metadata» «M» (minus) records getting skipped that inflate winter temperatures, differences in sea records from different measuring techniques, sea records vice land records, extrapolated land records over hundreds of km, surface temperature errors from lousy stations and lousy maintenance of surface records and stations, false and malicious time - of - observation bias changes in the information.)

NASA's «GISS» temp uses land and ocean - based thermometers which measure «different parts of the system [UHI affected parking lots, asphalt heat sinks, AC exhaust air vents], different signal to noise ratio [we bias toward warm stations], different structural uncertainty [we «homogenise» our data set to cool the past and warm the present to fit the global warming narrative].»

What the UHI accomplishes is, it gives a bias toward higher temperatures, due to the placement of thermometers in relation to the UHI effects.

These surface networks have had so many changes over time that the number of stations that have been moved, had their time of observation changed, had equipment changes, maintenance issues, or have been encroached upon by micro site biases and / or UHI using the raw data for all stations on a national scale or even a global scale gives you a result that is no longer representative of the actual measurements, there is simply too much polluted data.

If you drop the stations with less anomaly, and keep the ones with more warming as gauged by their anomaly, UHI or not, and use their anomaly, now transposed to the grid stations dropped, you may have problems and a biased warming.

How do we identify stations biased by UHI so we can prove they haven't effected that global record?

Science would conduct experiments and measure the biases (like UHI and station siting) and subtract the measured biases out of the data.

And, when you consider the warming bias in the surface temperatures (the UHI effect), it smells like the Left's dogma really cut the cheese.

I have always been amused at the thought that the 1960 deviationist tree rings might well have been right and that the grafted on instrumental record was simply a product of confirmation bias in the temp adjustments and, of course, Jones getting the UHI completely wrong (and then having his raw Chinese data «lost».

Oh Zeke, your attempts to justify your «adjustments» but completely ignoring the most obvious bias, UHI effect, tells me you are being rather disingenuous with your protestations that everything is OK with the data.

So, as I see it, the key issues are UHI, the micro sites and the non exisiting stations creating a warming bias by being included in the US record and possibly globally.

Root cause: the systemic bias in the land temperature record due the UHI effect, erroneous adjustments to the data and simply making up data were non exists to come up with an imaginary average global temperature.

UHI is a real problem, and without that correction the global trends would be biased high.

So even I, a skeptic, would expect a disproportionate number of the all - time high temperatures to be in the last decade, particularly without UHI correction and with the bias discussed above.

We really need to quantify UHI plus station loss plus siting probs plus sensor biases.

REPLY: Easier said than done - the problem is that only a handful have been identified in the USA that are free from UHI and siting biases, and we haven't even begun to look at the entire world.