Archives par mot-clé : Temperature

The Vostok Ice Core: Temperature, CO2 and CH4

by Euan Means, December 12, 2014


In their seminal paper on the Vostok Ice Core, Petit et al (1999) [1] note that CO2 lags temperature during the onset of glaciations by several thousand years but offer no explanation. They also observe that CH4 and CO2 are not perfectly aligned with each other but offer no explanation. The significance of these observations are therefore ignored. At the onset of glaciations temperature drops to glacial values before CO2 begins to fall suggesting that CO2 has little influence on temperature modulation at these times.

See also here

Global versus Greenland Holocene Temperatures

by Andy May, June 19, 2017 i


Last week, I posted a global temperature reconstruction based mostly on Marcott, et al. 2013 proxies. The post can be found here. In the comments on the Wattsupwiththat post there was considerable discussion about the difference between my Northern Hemisphere mid-latitude (30°N to 60°N) and the GISP2 Richard Alley central Greenland temperature reconstruction (see here for the reference and data). See the comments by Dr. Don Easterbrook and Joachim Seifert (weltklima) here and here, as well as their earlier comments.

Climate cycles and their extrapolation into the future

by Dr. Dietrich Koelle, February 2, 2015 in NoTricksZone


As the reconstruction of the climate’s development in the past by proxy data shows, there’s a series of temperature cycles that appear to be unknown, or ignored by many climate scientists. Among these are the larger climate cycles of 150 million to 180 million years (see Part 1 and Part 2), but also the shorter and for us the more important following cycles:

1000 years (900-1100)    Suess cycle with +/-  0.65°C
230 years (230-250)        deVries cycle with +/-  0.30°C
65  years (60-65)              Ocean cycles with +/- 0.25°C

 

A Holocene Temperature Reconstruction Part 4: The global reconstruction

by Andy May, June 9, 2017 in WUWT


In previous posts (here, here and here), we have shown reconstructions for the Antarctic, Southern Hemisphere mid-latitudes, the tropics, the Northern Hemisphere mid-latitudes, and the Arctic. Here we combine them into a simple global temperature reconstruction. The five regional reconstructions are shown in figure 1. The R code to map the proxy locations, the references and metadata for the proxies, and the global reconstruction spreadsheet can be downloaded here

A Holocene Temperature Reconstruction Part 3: The NH and Arctic

by Andy May, June 8, 2017 in WUWT


As we did in the previous two posts, we will examine each proxy and reject any that have an average time step greater than 130 years or if it does not cover at least part of the Little Ice Age (LIA) and the Holocene Climatic Optimum (HCO). We are looking for coverage from 9000 BP to 500 BP or very close to these values. Only simple statistical techniques that are easy to explain will be used.

 

The Correlation of Seismic Activity and Recent Global Warming

by Arthur Viterito, April 25, 2016 in J. of Earth Sc. & Climatic Change


Earth’s climate is a remarkably “noisy” system, driven by scores of oscillators, feedback mechanisms, and radiative forcings. Amidst all this noise, identifying a solitary input to the system (i.e., HGFA MAG4/6 seismic activity as a proxy for geothermal heat flux) that explains 62% of the variation in the earth’s surface temperature is a significant finding. Additionally, the 1997/1998 SIENA was a strong signal for subsequent global warming, and this type of seismic jump may provide valuable predictive information

Study: ‘Heat island’ effect could double climate change costs for world’s cities

by Anthony Watts, May 30, 2017 in WUWT


From the UNIVERSITY OF SUSSEX and overheated climate science department, comes a claim that just doesn’t seem plausible, suggesting that in the future, nearly 11% of a “worst-off city” gross domestic product would be consumed by UHI boosted climate change. On the other hand, the study is by Dr. Richard Tol, who is well respected by the climate skeptic community. He does have a point about “the effects of uncontrolled urban heat islands”

Overheated cities face climate change costs at least twice as big as the rest of the world because of the ‘urban heat island’ effect, new research shows.

Extreme temperatures in Southeast Asia caused by El Niño and worsened by global warming

by K. Thirumalai et al., June 6, 2017, in Nature Communication


In April 2016, southeast Asia experienced surface air temperatures (SATs) that surpassed national records, exacerbated energy consumption, disrupted agriculture and caused severe human discomfort. Here we show using observations and an ensemble of global warming simulations the combined impact of the El Niño/Southern Oscillation (ENSO) phenomenon and long-term warming on regional SAT extremes. We find a robust relationship between ENSO and southeast Asian SATs wherein virtually all April extremes occur during El Niño years.

Paris climate promises will reduce temperatures by just 0.05°C in 2100

by Bjorn Lomborg, June 2017

Even if we assume that these promises would be extended for another 70 years, there is still little impact: if every nation fulfills every promise by 2030, and continues to fulfill these promises faithfully until the end of the century, and there is no ‘CO₂ leakage’ to non-committed nations, the entirety of the Paris promises will reduce temperature rises by just 0.17°C (0.306°F) by 2100.

….

Where is the paper published?

The peer-reviewed paper is published in the upcoming issue of Global Policy journal (November 2015). You can access the article online here.

US Summers Are Getting Much Cooler

by Tony Heller, June 3, 2017


Summer is here, and climate alarmists are about to bombard us with claims that global warming is going to burn us up. The data shows the exact opposite. There are 693 USHCN stations which were active in both 1920 and 2016. I ran statistics on this stable group of stations.

The average summer maximum temperature in the US is down about one degree since the 1920’s.

A Holocene Temperature Reconstruction Part 1: the Antarctic

by Andy May, June1, 2017


The Marcott, et al. 2013 worldwide reconstruction has its problems, but many of the proxies used in the reconstruction are quite good and very usable.

The Antarctic reconstruction created here is comparable to previous temperature reconstructions, especially those focusing on eastern Antarctica. It shows two climatic optima, one from 11500 BP to 9000 BP and another from 6000 BP to 3000 BP. In eastern Antarctica, using our proxies, the later optimum is warmer. But, in other areas the earlier optimum is warmer, however, the difference is small

A paleo-perspective on ocean heat content: Lessons from the Holocene and Common Era

by Yair Rosenthal et al., January 1, 2017


 

Here we review proxy records of intermediate water temperatures from sediment cores in the equatorial Pacific and northeastern Atlantic Oceans, spanning 10,000 years beyond the instrumental record.

These records suggests that intermediate waters were 1.5–2 °C warmer during the Holocene Thermal Maximum than in the last century.

Intermediate water masses cooled by 0.9 °C from the Medieval Climate Anomaly to the Little Ice Age.

 

Video: analysis of NASA data shows modern temperature trends are not unusual

by Michael Thomas c/o Anthony Watts, May 10, 2017


An important aspect of the climate change debate can be summed up like this: “One position holds that medieval warm temperatures reached levels similar to the late twentieth century and maintained that the LIA was very cold, while another position holds that past variability was less than present extremes and that the temperature rise of recent decades is unmatched”. This video challenges whether the rise of recent decades is unmatched.

There Has Been No ‘Global’ Warming In The Southern Hemisphere, Equatorial Regions

by Kenneth Richard, May 4, 2017


According to overseers of the long-term instrumental temperature data, the Southern Hemisphere record is “mostly made up”.  This is due to an extremely limited number of available measurements both historically and even presently from the south pole to the equatorial regions.

Below is an actual e-mail conversation between the Climate Research Unit’s Phil Jones and climate scientist Tom Wigley.  Phil Jones is the one who is largely responsible for making up the 1850-present temperature data for the Met Office in the UK (HadCRUT).

 

Are Claimed Global Record-Temperatures Valid?

by Clyde Spencer, April 12, 2017


In summary, there are numerous data handling practices, which climatologists generally ignore, that seriously compromise the veracity of the claims of record average-temperatures, and are reflective of poor science. The statistical significance of temperature differences with 3 or even 2 significant figures to the right of the decimal point is highly questionable. One is not justified in using the approach of calculating the Standard Error of the Mean to improve precision, by removing random errors, because there is no fixed, single value that random errors cluster about. The global average is a hypothetical construct that doesn’t exist in Nature. Instead, temperatures are changing, creating variable, systematic-like errors. Real scientists are concerned about the magnitude and origin of the inevitable errors in their measurements.

Also : Perspective Needed; Time to Identify Variations in Natural Climate Data that Exceed the Claimed Human CO2 Warming Effect

Paris climate promises will reduce temperatures by just 0.05°C in 2100 (Press release)

by Bjorn Lomborg, April 2017


The climate impact of all Paris INDC promises is minuscule: if we measure the impact of every nation fulfilling every promise by 2030, the total temperature reduction will be 0.048°C (0.086°F) by 2100.

Even if we assume that these promises would be extended for another 70 years, there is still little impact: if every nation fulfills every promise by 2030, and continues to fulfill these promises faithfully until the end of the century, and there is no ‘CO₂ leakage’ to non-committed nations, the entirety of the Paris promises will reduce temperature rises by just 0.17°C (0.306°F) by 2100.