date: Wed Feb 20 12:15:57 2008 from: Phil Jones subject: Re: Your ENSO series to: David Thompson Dave, Will send on your details to the seminar organizer here. The week of April 28 - May 2 is OK for me. I hope this is what you meant by last week. A few thoughts on the plots. 1. There isn't a drop off in land data around 1945 - nor during WW2. So this is different from the ocean data. Most series are complete or have been slightly infilled during the period in Europe. Berlin for example only missed one day's T obs in April 45. 2. Fuego could be underestimated. 3. It could also be that sulphate emissions were very high at this time - late 60s, early 70s. I'll await the text ! Cheers Phil At 16:18 19/02/2008, you wrote: Hi Phil, I'd enjoy visiting.... how does the first or last week of April look to you? As for some new results: I've attached two figures. Both focus on the land data. The first figure includes 4 time series. From top to bottom: the global-mean land data (CRUTEM 3); the ENSO fit; the COWL fit; the residual global-mean time series. There is nothing here you haven't seen before - the residual land time series is identical to the one in the Nature paper. As we've discussed, the residual land time series highlights the signature of the volcanos. And as far as low frequency variability goes: the residual land time series supports the IPCC contention that the global warmed from ~1900-1940; did not warm from ~1940-1980; and warmed substantially from 1980 to present. OK.... so now I'm going to play with removing the volcanic signal. There are a lot of ways to do this, and I haven't settled on the best method. For now, I am driving the simple climate model I've been using for ENSO with the Ammann et al. volcanic forcing time series. I get identical results using Crowley's estimate and Sato's estimate. The figure on page 2 shows the effect of removing the volcanic signal. From top to bottom: the the global-mean residual land time series (repeated from the previous figure); the volcanic fit; the 'ENSO/COWL/Volcano' residual land time series. Some key points: 1. the volcanic fit isn't perfect, but captures most of the volcanic signal. 2. the residual time series (bottom of Fig 2) is interesting. If you look closely, it suggests the globe has warmed continuously since 1900 with two exceptions: a 'bite' in the 1970s, and a downwards 'step' in 1945. The step in 1945 is not as dramatic as the step in the ocean data. But it's there. (I'm guessing the corresponding change in variance is due to a sudden increase in data coverage). 3. the volcanic fit highlights the fact that the lack of warming in the middle part of the century comes from only two features: the step in 45 and Agung. When Agung is removed, land temperatures march upwards from 1945-1970 (Fig 2 bottom). 4. the bite in the 1970s could be due to an underestimate of the impact of Fuego (the bite is also evident in the SST data). What do you think? The step in 1945 is not as dramatic as the step in the SST data. But it's certainly there. It's evident in the COWL/ENSO residual time series (top of Fig 2): removing Agung simply clarifies that without the step temperatures marched steadily upwards from 1900-1970. -Dave  On Feb 19, 2008, at 1:28 PM, Phil Jones wrote: Dave, Thanks. Before seeing what you send, I think I'll find it harder to believe something is wrong with the land data. I can be convinced though.... So you're in Reading now. Do you still want to come up to distant Norwich at some point and also give a talk? Cheers Phil At 16:55 18/02/2008, you wrote: Phil, I'm really sorry for the delay; my family and I have been in transit from the US to the UK this past week, and it's taken a bit for us to get settled. I've attached the ENSO index I've been using. The first month is Jan 1850; the last is Dec 2006. The time series has a silly number of sig figures - that's just how Matlab wanted to save it. The data are in K and are scaled as per the fit to the global-mean (as in the paper). I've got some new results regarding the land data... I'll think you'll find them interesting. I'll pass them along in the next day or so... the main point is that I suspect the land data might also have some spurious cooling in the middle part of the century. More to come.... -Dave  On Feb 14, 2008, at 12:35 PM, Phil Jones wrote: David, For a presentation I'm due to make in a few months, can you send me the ENSO and the COWL series that are in Figure 1 in the paper. I'm not sure what I will do with COWL, but I want to compare your ENSO with some of the ENSO-type indices I have. These seem monthly from about the 1860s or maybe earlier. Cheers Phil At 16:49 07/02/2008, you wrote: So it made it past the first hurdle, which is good. My hunch is that the paper will fare OK in review, but you never know with Nature. And it's possible a reviewer will insist on our providing a correction... anyway, we'll see... -Dave Begin forwarded message: From: j.thorpe@nature.com Date: February 7, 2008 3:44:07 AM PST To: davet@atmos.colostate.edu Subject: Nature 2008-01-00939 out to review Dear Professor Thompson, Thank you for submitting your manuscript entitled "A discontinuity in the time series of global-mean surface temperature" to Nature. I am pleased to tell you that we are sending your paper out for review. We will be in touch again as soon as we have received comments from our reviewers. Yours sincerely Nichola O'Brien Staff Nature For Dr. Joanna Thorpe Associate Editor, Nature Nature Publishing Group -- [1]http://www.nature.com/nature The Macmillan Building, 4 Crinan Street, London N1 9XW, UK Tel +44 20 7833 4000; Fax +44 20 7843 4596; nature@nature.com 968 National Press Building, Washington DC 20045-1938, USA Tel +1 202 737 2355; Fax +1 202 628 1609; nature@naturedc.com * Please see NPG's author and referees' website ( [2]www.nature.com/ authors) for information about and links to policies, services and author benefits. See also [3]http://blogs.nature.com/nautilus, our blog for authors, and [4]http://blogs.nature.com/peer-to-peer, our blog about peer-review. This email has been sent through the NPG Manuscript Tracking System NY-610A-NPG&MTS ------------------------------------------------------------------- - ------------------------------------------------------------------- - David W. J. Thompson [5]www.atmos.colostate.edu/~davet Dept of Atmospheric Science Colorado State University Fort Collins, CO 80523 USA Phone: 970-491-3338 Fax: 970-491-8449 Prof. Phil Jones Climatic Research Unit Telephone +44 (0) 1603 592090 School of Environmental Sciences Fax +44 (0) 1603 507784 University of East Anglia Norwich Email p.jones@uea.ac.uk NR4 7TJ UK -------------------------------------------------------------------- -- ------ -------------------------------------------------------------------- -------------------------------------------------------------------- David W. J. Thompson [6]www.atmos.colostate.edu/~davet Dept of Atmospheric Science Colorado State University Fort Collins, CO 80523 USA Phone: 970-491-3338 Fax: 970-491-8449 Phil, I'm really sorry for the delay; my family and I have been in transit from the US to the UK this past week, and it's taken a bit for us to get settled. I've attached the ENSO index I've been using. The first month is Jan 1850; the last is Dec 2006. The time series has a silly number of sig figures - that's just how Matlab wanted to save it. The data are in K and are scaled as per the fit to the global-mean (as in the paper). I've got some new results regarding the land data... I'll think you'll find them interesting. I'll pass them along in the next day or so... the main point is that I suspect the land data might also have some spurious cooling in the middle part of the century. More to come.... -Dave On Feb 14, 2008, at 12:35 PM, Phil Jones wrote: David, For a presentation I'm due to make in a few months, can you send me the ENSO and the COWL series that are in Figure 1 in the paper. I'm not sure what I will do with COWL, but I want to compare your ENSO with some of the ENSO-type indices I have. These seem monthly from about the 1860s or maybe earlier. Cheers Phil At 16:49 07/02/2008, you wrote: So it made it past the first hurdle, which is good. My hunch is that the paper will fare OK in review, but you never know with Nature. And it's possible a reviewer will insist on our providing a correction... anyway, we'll see... -Dave Begin forwarded message: From: j.thorpe@nature.com Date: February 7, 2008 3:44:07 AM PST To: davet@atmos.colostate.edu Subject: Nature 2008-01-00939 out to review Dear Professor Thompson, Thank you for submitting your manuscript entitled "A discontinuity in the time series of global-mean surface temperature" to Nature. I am pleased to tell you that we are sending your paper out for review. We will be in touch again as soon as we have received comments from our reviewers. Yours sincerely Nichola O'Brien Staff Nature For Dr. Joanna Thorpe Associate Editor, Nature Nature Publishing Group -- [7]http://www.nature.com/nature The Macmillan Building, 4 Crinan Street, London N1 9XW, UK Tel +44 20 7833 4000; Fax +44 20 7843 4596; nature@nature.com 968 National Press Building, Washington DC 20045-1938, USA Tel +1 202 737 2355; Fax +1 202 628 1609; nature@naturedc.com * Please see NPG's author and referees' website ( [8]www.nature.com/authors) for information about and links to policies, services and author benefits. See also [9]http:// blogs.nature.com/nautilus, our blog for authors, and [10]http:// blogs.nature.com/peer-to-peer, our blog about peer-review. This email has been sent through the NPG Manuscript Tracking System NY-610A-NPG&MTS ------------------------------------------------------------------- - ------------------------------------------------------------------- - David W. J. Thompson [11]www.atmos.colostate.edu/~davet Dept of Atmospheric Science Colorado State University Fort Collins, CO 80523 USA Phone: 970-491-3338 Fax: 970-491-8449 Prof. Phil Jones Climatic Research Unit Telephone +44 (0) 1603 592090 School of Environmental Sciences Fax +44 (0) 1603 507784 University of East Anglia Norwich Email p.jones@uea.ac.uk NR4 7TJ UK -------------------------------------------------------------------- -------- -------------------------------------------------------------------- -------------------------------------------------------------------- David W. J. Thompson [12]www.atmos.colostate.edu/~davet Dept of Atmospheric Science Colorado State University Fort Collins, CO 80523 USA Phone: 970-491-3338 Fax: 970-491-8449 Prof. Phil Jones Climatic Research Unit Telephone +44 (0) 1603 592090 School of Environmental Sciences Fax +44 (0) 1603 507784 University of East Anglia Norwich Email p.jones@uea.ac.uk NR4 7TJ UK ---------------------------------------------------------------------- ------ -------------------------------------------------------------------- -------------------------------------------------------------------- David W. J. Thompson [13]www.atmos.colostate.edu/~davet Dept of Atmospheric Science Colorado State University Fort Collins, CO 80523 USA Phone: 970-491-3338 Fax: 970-491-8449 Hi Phil, I'd enjoy visiting.... how does the first or last week of April look to you? As for some new results: I've attached two figures. Both focus on the land data. The first figure includes 4 time series. From top to bottom: the global-mean land data (CRUTEM 3); the ENSO fit; the COWL fit; the residual global-mean time series. There is nothing here you haven't seen before - the residual land time series is identical to the one in the Nature paper. As we've discussed, the residual land time series highlights the signature of the volcanos. And as far as low frequency variability goes: the residual land time series supports the IPCC contention that the global warmed from ~1900-1940; did not warm from ~1940-1980; and warmed substantially from 1980 to present. OK.... so now I'm going to play with removing the volcanic signal. There are a lot of ways to do this, and I haven't settled on the best method. For now, I am driving the simple climate model I've been using for ENSO with the Ammann et al. volcanic forcing time series. I get identical results using Crowley's estimate and Sato's estimate. The figure on page 2 shows the effect of removing the volcanic signal. From top to bottom: the the global-mean residual land time series (repeated from the previous figure); the volcanic fit; the 'ENSO/COWL/Volcano' residual land time series. Some key points: 1. the volcanic fit isn't perfect, but captures most of the volcanic signal. 2. the residual time series (bottom of Fig 2) is interesting. If you look closely, it suggests the globe has warmed continuously since 1900 with two exceptions: a 'bite' in the 1970s, and a downwards 'step' in 1945. The step in 1945 is not as dramatic as the step in the ocean data. But it's there. (I'm guessing the corresponding change in variance is due to a sudden increase in data coverage). 3. the volcanic fit highlights the fact that the lack of warming in the middle part of the century comes from only two features: the step in 45 and Agung. When Agung is removed, land temperatures march upwards from 1945-1970 (Fig 2 bottom). 4. the bite in the 1970s could be due to an underestimate of the impact of Fuego (the bite is also evident in the SST data). What do you think? The step in 1945 is not as dramatic as the step in the SST data. But it's certainly there. It's evident in the COWL/ENSO residual time series (top of Fig 2): removing Agung simply clarifies that without the step temperatures marched steadily upwards from 1900-1970. -Dave On Feb 19, 2008, at 1:28 PM, Phil Jones wrote: Dave, Thanks. Before seeing what you send, I think I'll find it harder to believe something is wrong with the land data. I can be convinced though.... So you're in Reading now. Do you still want to come up to distant Norwich at some point and also give a talk? Cheers Phil At 16:55 18/02/2008, you wrote: Phil, I'm really sorry for the delay; my family and I have been in transit from the US to the UK this past week, and it's taken a bit for us to get settled. I've attached the ENSO index I've been using. The first month is Jan 1850; the last is Dec 2006. The time series has a silly number of sig figures - that's just how Matlab wanted to save it. The data are in K and are scaled as per the fit to the global-mean (as in the paper). I've got some new results regarding the land data... I'll think you'll find them interesting. I'll pass them along in the next day or so... the main point is that I suspect the land data might also have some spurious cooling in the middle part of the century. More to come.... -Dave  On Feb 14, 2008, at 12:35 PM, Phil Jones wrote: David, For a presentation I'm due to make in a few months, can you send me the ENSO and the COWL series that are in Figure 1 in the paper. I'm not sure what I will do with COWL, but I want to compare your ENSO with some of the ENSO-type indices I have. These seem monthly from about the 1860s or maybe earlier. Cheers Phil At 16:49 07/02/2008, you wrote: So it made it past the first hurdle, which is good. My hunch is that the paper will fare OK in review, but you never know with Nature. And it's possible a reviewer will insist on our providing a correction... anyway, we'll see... -Dave Begin forwarded message: From: [14]j.thorpe@nature.com Date: February 7, 2008 3:44:07 AM PST To: [15]davet@atmos.colostate.edu Subject: Nature 2008-01-00939 out to review Dear Professor Thompson, Thank you for submitting your manuscript entitled "A discontinuity in the time series of global-mean surface temperature" to Nature. I am pleased to tell you that we are sending your paper out for review. We will be in touch again as soon as we have received comments from our reviewers. Yours sincerely Nichola O'Brien Staff Nature For Dr. Joanna Thorpe Associate Editor, Nature Nature Publishing Group -- [16]http://www.nature.com/nature The Macmillan Building, 4 Crinan Street, London N1 9XW, UK Tel +44 20 7833 4000; Fax +44 20 7843 4596; [17]nature@nature.com 968 National Press Building, Washington DC 20045-1938, USA Tel +1 202 737 2355; Fax +1 202 628 1609; [18]nature@naturedc.com * Please see NPG's author and referees' website ( [19]www.nature.com/ authors) for information about and links to policies, services and author benefits. See also [20]http://blogs.nature.com/nautilus, our blog for authors, and [21]http://blogs.nature.com/peer-to-peer, our blog about peer-review. This email has been sent through the NPG Manuscript Tracking System NY-610A-NPG&MTS -------------------------------------------------------------------- -------------------------------------------------------------------- David W. J. Thompson [22]www.atmos.colostate.edu/~davet Dept of Atmospheric Science Colorado State University Fort Collins, CO 80523 USA Phone: 970-491-3338 Fax: 970-491-8449 Prof. Phil Jones Climatic Research Unit Telephone +44 (0) 1603 592090 School of Environmental Sciences Fax +44 (0) 1603 507784 University of East Anglia Norwich Email [23]p.jones@uea.ac.uk NR4 7TJ UK ---------------------------------------------------------------------- ------ -------------------------------------------------------------------- -------------------------------------------------------------------- David W. J. Thompson [24]www.atmos.colostate.edu/~davet Dept of Atmospheric Science Colorado State University Fort Collins, CO 80523 USA Phone: 970-491-3338 Fax: 970-491-8449 Phil, I'm really sorry for the delay; my family and I have been in transit from the US to the UK this past week, and it's taken a bit for us to get settled. I've attached the ENSO index I've been using. The first month is Jan 1850; the last is Dec 2006. The time series has a silly number of sig figures - that's just how Matlab wanted to save it. The data are in K and are scaled as per the fit to the global-mean (as in the paper). I've got some new results regarding the land data... I'll think you'll find them interesting. I'll pass them along in the next day or so... the main point is that I suspect the land data might also have some spurious cooling in the middle part of the century. More to come.... -Dave On Feb 14, 2008, at 12:35 PM, Phil Jones wrote: David, For a presentation I'm due to make in a few months, can you send me the ENSO and the COWL series that are in Figure 1 in the paper. I'm not sure what I will do with COWL, but I want to compare your ENSO with some of the ENSO-type indices I have. These seem monthly from about the 1860s or maybe earlier. Cheers Phil At 16:49 07/02/2008, you wrote: So it made it past the first hurdle, which is good. My hunch is that the paper will fare OK in review, but you never know with Nature. And it's possible a reviewer will insist on our providing a correction... anyway, we'll see... -Dave Begin forwarded message: From: [25]j.thorpe@nature.com Date: February 7, 2008 3:44:07 AM PST To: [26]davet@atmos.colostate.edu Subject: Nature 2008-01-00939 out to review Dear Professor Thompson, Thank you for submitting your manuscript entitled "A discontinuity in the time series of global-mean surface temperature" to Nature. I am pleased to tell you that we are sending your paper out for review. We will be in touch again as soon as we have received comments from our reviewers. Yours sincerely Nichola O'Brien Staff Nature For Dr. Joanna Thorpe Associate Editor, Nature Nature Publishing Group -- [27]http://www.nature.com/nature The Macmillan Building, 4 Crinan Street, London N1 9XW, UK Tel +44 20 7833 4000; Fax +44 20 7843 4596; [28]nature@nature.com 968 National Press Building, Washington DC 20045-1938, USA Tel +1 202 737 2355; Fax +1 202 628 1609; [29]nature@naturedc.com * Please see NPG's author and referees' website ( [30]www.nature.com/authors) for information about and links to policies, services and author benefits. See also [31]http://blogs.nature.com/nautilus, our blog for authors, and [32]http://blogs.nature.com/peer-to-peer, our blog about peer-review. This email has been sent through the NPG Manuscript Tracking System NY-610A-NPG&MTS -------------------------------------------------------------------- -------------------------------------------------------------------- David W. J. Thompson [33]www.atmos.colostate.edu/~davet Dept of Atmospheric Science Colorado State University Fort Collins, CO 80523 USA Phone: 970-491-3338 Fax: 970-491-8449 Prof. Phil Jones Climatic Research Unit Telephone +44 (0) 1603 592090 School of Environmental Sciences Fax +44 (0) 1603 507784 University of East Anglia Norwich Email [34]p.jones@uea.ac.uk NR4 7TJ UK ---------------------------------------------------------------------------- -------------------------------------------------------------------- -------------------------------------------------------------------- David W. J. Thompson [35]www.atmos.colostate.edu/~davet Dept of Atmospheric Science Colorado State University Fort Collins, CO 80523 USA Phone: 970-491-3338 Fax: 970-491-8449 Prof. Phil Jones Climatic Research Unit Telephone +44 (0) 1603 592090 School of Environmental Sciences Fax +44 (0) 1603 507784 University of East Anglia Norwich Email [36]p.jones@uea.ac.uk NR4 7TJ UK ---------------------------------------------------------------------------- -------------------------------------------------------------------- -------------------------------------------------------------------- David W. J. Thompson [37]www.atmos.colostate.edu/~davet Dept of Atmospheric Science Colorado State University Fort Collins, CO 80523 USA Phone: 970-491-3338 Fax: 970-491-8449 Prof. Phil Jones Climatic Research Unit Telephone +44 (0) 1603 592090 School of Environmental Sciences Fax +44 (0) 1603 507784 University of East Anglia Norwich Email p.jones@uea.ac.uk NR4 7TJ UK ----------------------------------------------------------------------------