RealClimate

Climate science from climate scientists...

You are here: Home / Archives for RC Forum

RC Forum

Unforced variations: Jan 2020

by

The new open thread on climate science for a new year, and a new decade – perhaps the Soaring Twenties? What precisely will be soaring is yet to be decided though.

Two things will almost certainly go up – CO2 emissions and temperatures:

But maybe also ambition, determination, and changes that will lead to reduced emissions in future? Fingers crossed.

There was no pause

by

I think that the idea of a pause in the global warming has been a red herring ever since it was suggested, and we have commented on this several times here on RC: On how data gaps in some regions (eg. the Arctic) may explain an underestimation of the recent warming. We have also explained how natural oscillations may give the impression of a faux pause. Now, when we know the the global mean temperature for 2016, it’s even more obvious.

Easterling and Wehner (2009) explained that it is not surprising to see some brief periods with an apparent decrease in a temperature record that increases in jumps and spurts, and Foster and Rahmstorf (2012) showed in a later paper how temperature data from the most important observations show consistent global warming trends when known short-term influences such as El Niño Southern oscillation (ENSO), volcanic aerosols and solar variability are accounted for.

A recent paper by Hausfather et al. (2017) adds little new to our understanding, although it confirms that there has not been a recent “hiatus” in the global warming. However, if there are doubts about a physical condition, then further scientific research is our best option for establishing the facts. This is exactly what this recent study did.

The latest findings confirm the results of Karl et al. 2015 from the National Oceanic Atmospheric Administration (NOAA), which Gavin described in a previous post here on RC. The NOAA analysis received unusual attention because of the harassment it drew from the chair of the US House Science Committee and the subpoena demand for emails.

[Read more…] about There was no pause

References

  1. D.R. Easterling, and M.F. Wehner, "Is the climate warming or cooling?", Geophysical Research Letters, vol. 36, 2009. http://dx.doi.org/10.1029/2009GL037810
  2. G. Foster, and S. Rahmstorf, "Global temperature evolution 1979–2010", Environmental Research Letters, vol. 6, pp. 044022, 2011. http://dx.doi.org/10.1088/1748-9326/6/4/044022
  3. Z. Hausfather, K. Cowtan, D.C. Clarke, P. Jacobs, M. Richardson, and R. Rohde, "Assessing recent warming using instrumentally homogeneous sea surface temperature records", Science Advances, vol. 3, 2017. http://dx.doi.org/10.1126/sciadv.1601207
  4. T.R. Karl, A. Arguez, B. Huang, J.H. Lawrimore, J.R. McMahon, M.J. Menne, T.C. Peterson, R.S. Vose, and H. Zhang, "Possible artifacts of data biases in the recent global surface warming hiatus", Science, vol. 348, pp. 1469-1472, 2015. http://dx.doi.org/10.1126/science.aaa5632

Climatology and meteorology are your friends

by

The Norwegian Meteorological institute has celebrated its 150th anniversary this year. It was founded to provide weather data and tentative warnings to farmers, sailors, and fishermen. The inception of Norwegian climatology in the mid-1800s started with studies of geographical climatic variations to adapt important infrastructure to the ambient climate. The purpose of the meteorology and climatology was to protect lives and properties.

[Read more…] about Climatology and meteorology are your friends

Climate change is coming to a place near you

by

What are the local consequences of a continued global warming? And what kind of future climate can you expect for you children? Do we expect more extreme events, and will a global warming affect the statistics of storms? Another question is how the local changes matters for local communities and the ecosystem.

It may be contrary to most people’s impression. We have a clearer picture of future climate changes on a global scale than of the local consequences associated with a global warming. And we know why.

[Read more…] about Climate change is coming to a place near you

The IPCC SREX: the report is finally out.

by

Some of us have been waiting quite a while now, especially since the ‘road tour’ meant to present the Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation starting in Oslo on January 24th this year. The summary for policymakers (SPM) was released already in 18 November 2011 (Kampala) and now the report is finally available (link).

[Read more…] about The IPCC SREX: the report is finally out.

Free speech and academic freedom

by

Update: Some related concerns from deepclimate.org, if these claims can be verified.

In a recent interview for a Norwegian magazine (Teknisk Ukeblad, 0412), the IPCC chair Rajendra Kumar Pachauri told the journalist that he had received death threats in connection with his role as a head for the IPCC. There have also been recent reports of threats and harassment of climate scientists for their stance on climate change (Kerry Emanuel. Katharine Hayhoe, Australian climate scientists, Phil Jones, Barton campaign, and Inhofe’s black list).

[Read more…] about Free speech and academic freedom

Please, show us your code

by

The 1991 Science paper by Friis-Christensen & Lassen, work by Henrik Svensmark (Physical Review Letters), and calculations done by Scafetta & West (in the journals Geophysical Research Letters, Journal of Geophysical Research, and Physics Today) have inspired the idea that the recent warming is due to changes in the sun, rather than greenhouse gases.

We have discussed these papers before here on RealClimate (here, here, and here), and I think it’s fair to say that these studies have been fairly influential one way or the other. But has anybody ever seen the details of the methods used, or the data? I believe that a full disclosure of their codes and data would really boost the confidence in their work, if they were sound. So if they believe so strongly that their work is solid, why not more transparency?

[Read more…] about Please, show us your code