GISS Spackle and Caulk

Guest post by John Goetz
Cross posted from Climate Audit

Earlier this year I did a post on the amount of estimation done to the GHCN temperature record by GISS before generating zonal and global averages. A graphic I posted compared the amount of real temperature data with the amount of estimation over time. To read the graphic, consider 2000 as an example. As of February 7, 2008 there were 3159 station records in the GHCN data with an entry for the year 2000. Of those station records, 62% were complete and an annual average could be fully calculated. Another 29% were incomplete, but contained enough monthly data that the GISS estimation method kicked in. The final 9% were so incomplete that no estimation could be done.

What I did not explore at the time and would like to look more closely here is the accuracy of the estimation. One would hope with so much infilling going on that the accuracy would be rather high (I will leave the determination of “high accuracy” for a later time). Because I did not have real data to compare with the GISS estimations, I took another approach. I used the GISS method to estimate real temperature data as if that data were missing.

Recall that GISS never explicitly estimates missing monthly temperatures. What they do is estimate seasonal averages when one monthly temperature is missing but the other two are present. Similarly, an annual temperature can be estimated when one seasonal value is missing but the other three are present. Using this methodology GISS can estimate an annual temperature when as many as six monthly values are missing.

While no explicit monthly estimate is recorded by GISS, it certainly can be derived from the seasonal estimate. I have shown several times a one-line equation that exactly reproduces the GISS seasonal estimate. Leaving a subsequent derivation as an exercise for the reader, the implied monthly estimate can be found from that equation and is expressed as follows:

where the average values for A, B, and C are calculated from all valid entries for the given month in a particular station record.

Now to test the estimation accuracy. In Connecticut, December 2006 was warmer than normal, but February 2007 was colder than normal. Looking at the records for Hartford, CT, we see the following monthly and seasonal temperatures:

Dec 2006: 3.3
Jan 2007: -0.3
Feb 2007: -4.6
DJF: -0.5

If the December 2006 record were missing from Hartford, GISS would estimate a value of -0.7 C, which would yield a seasonal average of -1.9 C. Similarly, if February 2007 were missing, GISS would estimate it at 1.7 C and produce a seasonal average of 1.6 C. That’s a 4.0 degree miss for Dec, a 6.3 degree miss for February, and a 3.5 degree swing at the seasonal level.

The winter of 06-07 in Connecticut was a bit of an oddball. I really wanted to know what the typical error looked like. To do that, I performed the same calculation on all GHCN v2.mean records.

NASA Sees Arctic Ocean Circulation Do an About-Face

NOTE: You may recall a story I posted some months ago titled: “NASA: It’s the wind” regarding Arctic wind circulation patterns and the way it drove sea ice further south into melt zones. Commenter Paul Marek brought this story to attention recently, and given the sea ice trend this summer, I thought it was worth bringing to light again. Then and now, “The results suggest not all the large changes seen in Arctic climate in recent years are a result of long-term trends associated with global warming. ” Given our less than predicted catastrophic sea ice loss this year, coupled with this study, it looks like Arctic ice could be on the mend. - Anthony

Click for Larger image
This shows contours of the trend in ocean bottom pressure from 2002 to 2006 as measured by GRACE along with hypothetical trends that would apply at the circles if ocean salinity reverted from 1990s values to climatological conditions over the same period.

NASA Sees Arctic Ocean Circulation Do an About-Face
November 13, 2007

PASADENA, Calif. – A team of NASA and university scientists has detected an ongoing reversal in Arctic Ocean circulation triggered by atmospheric circulation changes that vary on decade-long time scales. The results suggest not all the large changes seen in Arctic climate in recent years are a result of long-term trends associated with global warming.

The team, led by James Morison of the University of Washington’s Polar Science Center Applied Physics Laboratory, Seattle, used data from an Earth-observing satellite and from deep-sea pressure gauges to monitor Arctic Ocean circulation from 2002 to 2006. They measured changes in the weight of columns of Arctic Ocean water, from the surface to the ocean bottom. That weight is influenced by factors such as the height of the ocean’s surface, and its salinity. A saltier ocean is heavier and circulates differently than one with less salt.

The very precise deep-sea gauges were developed with help from the National Oceanic and Atmospheric Administration; the satellite is NASA’s Gravity Recovery and Climate Experiment (Grace). The team of scientists found a 10-millibar decrease in water pressure at the bottom of the ocean at the North Pole between 2002 and 2006, equal to removing the weight of 10 centimeters (four inches) of water from the ocean. The distribution and size of the decrease suggest that Arctic Ocean circulation changed from the counterclockwise pattern it exhibited in the 1990s to the clockwise pattern that was dominant prior to 1990.

Reporting in Geophysical Research Letters, the authors attribute the reversal to a weakened Arctic Oscillation, a major atmospheric circulation pattern in the northern hemisphere. The weakening reduced the salinity of the upper ocean near the North Pole, decreasing its weight and changing its circulation.

“Our study confirms many changes seen in upper Arctic Ocean circulation in the 1990s were mostly decadal in nature, rather than trends caused by global warming,” said Morison.

Urbanization raises the heat in Orange County, CA

UPDATE: I personally visited this station today, thanks to a family visit that coincidentally took me to within a couple of miles of this station. It’s on a rooftop at the fire station. I’ll have a complete report tomorrow, but here are some preliminary photos I’m submitting via WiFi at a local Starbucks a short distance away. - Anthony

  
Click thumbnails for larger images

From the Orange County Register:

Urbanization raises the heat in O.C.

August 7th, 2008, 2:00 pm by grobbins

The average annual temperature in Santa Ana has increased by 7.5 degrees in less than a century, a spike largely attributed to urbanization which has seen the city’s population climb from less than 15,000 to more than 350,000. The temperature has gone from a low of 59.7 degrees in 1920 to 67.2 in 1997, with yearly temperatures near the all-time high as recently as 2006.

“Santa Ana now has a lot more buildings, parking lots and streets, which absorb and hold heat, some of it through the night,” says Ivory Small, science officer at the San Diego office of the National Weather Service.

The NWS analyzed the city’s climate and weather based on daily temperature readings from the Santa Ana Fire Station, which has been recording temperatures since 1916. The upward trend is depicted here by Register illustrator Scott Brown.

Forecasters calculated the average yearly temperature by determining the average high and average low temperature for each month. Then they divided those figures by two and got the average monthly temperature. Then they added up the average temperature for January through December of each year and divided by 12, getting the average annual temperature.

Santa Ana’s population has been on a steady, and basically predictable, rise for decades. The average annual temperature also has risen steadily. But the temperature increase didn’t occur in a predictable,  incremental year-by-year pattern. There were lots of hiccups. For example, the average high for 1961 was 64.0 degrees. Three years earlier, the average high was 65 degrees.

Scientists say the average temperature didn’t smoothly rise year-by-year partly due to natural variability. In other words, some years are hotter than others because of  natural fluctuations in weather and climate.

But over the long-term, the average temperature has been going up in Santa Ana (click to enlarge image of the ‘city” in the 1920s.)

“The increase in temperatures in Santa Ana, as well as an increase in extreme heat days and in heat waves is primarily — about 60 percent — due to the ‘urban heat island effect,’ ” says Bill Patzert, a climatologist at the Jet Propulsion Laboratory in Pasadena. 

“Santa Ana is embedded in the dramatic urbanization or ‘extreme makeover’ of Orange County. More homes, lawns, shopping centers, traffic, freeways and agriculture, all absorbing and retaining solar radiation, making Santa Ana and Orange County warmer.

“On a larger scale, Orange County is atmospherically connected to our ever-expanding and warming Southern California megalopolis. Global warming due to increasing greenhouse gases is responsible for about 40 percent of the overall heating observed in Southern California. “

The view on AGW from the Australian

Key degrees of difference

Cameron Stewart, Associate editor | August 09, 2008

http://www.theaustralian.news.com.au/story/0,25197,24148862-11949,00.html 

HAS global warming stopped? The question alone is enough to provoke scorn from the mainstream scientific community and from the Government, which says the earth has never been hotter. But tell that to a new army of sceptics who have mushroomed on internet blog sites and elsewhere in recent months to challenge some of the most basic assumptions and claims of climate change science.

Their claims are provocative and contentious but they are also attracting attention, so much sothat mainstream scientists are being forced torespond.

The bloggers and others make several key claims. They say the way of measuring the world’s temperature is frighteningly imprecise and open to manipulation. They argue that far from becoming hotter, the world’s temperatures have cooled in the past decade, contrary to the overwhelming impression conveyed by scientists and politicians.

As such, they say there should be far greater scepticism towards the apocalyptic predictions about climate change. Even widely accepted claims, such as that made by Climate Change Minister Penny Wong that “the 12 hottest years in history have all been in the last 13 years”, are being openly challenged.

“She is just plain wrong,” says Jennifer Marohasy, a biologist and senior fellow of the Institute of Public Affairs. “It’s not a question of debate. What about the medieval warming period? The historical record shows they were growing wine in England, for goodness sake; come on. It is not disputed by anyone that the Vikings arrived in Greenland in AD900 and it was warmer than Greenland is now. What Penny Wong is doing is being selective and saying that is a long time ago.”

“…this year, there was an exceptional amount of ice -”

Click for larger image - Polarstern am Eisrand vor Nordost-Grönland

Photo: Martin Graeve, Alfred-Wegener-Institut

August 7-08 press release on work done from MV Polarstern in the northern Greenland Sea (between Svalbard and NE Greenland):

from Alfred Wegener Institute (AWI): http://idw-online.de/pages/de/news273425

a few excerpts, my abbreviated translation:

“this year, there was an exceptional amount of ice - according to expedition leader Prof. Gerhard Kattner. The extent reached from the high North southward to 74 degrees latitude. The main objective of the research cruise was to check 17 moorings with instruments that monitor temperature, salinity and currents of the water masses. AWI has been carrying out these unique high-latitude investigations since 1999. Observed 2008 temperatures are slightly lower than 2006 measurements, and there are preliminary indications of a return of the pacific water mass signature, which has been absent since 2004″

h/t to: Ulrich Lobsiger for the link and translation

NOAA: U.S. Temperature Above Normal in July

FOR IMMEDIATE RELEASE

Contact: John Leslie 301-713-2087, ext. 174

Aug. 8, 2008

NOAA: U.S. Temperature Above Normal in July  

July 2008 was the 30^th warmest July for the contiguous United States, based on records dating back to 1895, according to an analysis by NOAA’s National Climatic Data Center in Asheville, N.C. The average July temperature—74.9 degrees F—was 0.7 degrees above the 20^th century mean, based on preliminary data.

 

U.S. Temperature Highlights

 

• July temperatures were generally higher than average across the West and Northeast and below average in the Midwest.

 

• Five states (Conn., Mass., N.J., R.I. and Utah) were much warmer than average. Rhode Island had its sixth warmest July, and Massachusetts and Utah both had their eighth warmest July, based on statewide data going back to 1895. Six states (Ill., Ind., Ky., Mo., N.M. and W.Va.) were cooler than average.

 

• Based on NOAA’s Residential Energy Demand Temperature Index, contiguous U.S. temperature-related energy demand was approximately three percent above average in July.

 

U.S. Precipitation Highlights

July UAH Global Temperature Anomaly: up a bit and in general agreement with RSS

UAH (University of Alabama, Huntsville) Microwave Sounder Unit (MSU) lower troposphere global temperature anomaly data for July 2008 was published today and has moved a bit above the zero anomaly line, with a value of 0.048, up from -0.114 in June 2008

The global UAH ∆T from June to July 2008 was .162°C

UAH
2008 1 -0.046
2008 2 0.020
2008 3 0.094
2008 4 0.015
2008 5 -0.180
2008 6 -0.114
2008 7  0.048  

Click for a larger image
Reference: UAH lower troposphere data

Just like with the RSS global temperature anomaly data, I rather expected it to go up a bit, given that La Nina has diminished, plus the NH has a greater landmass than the SH, and we are in summer.

Click for a large image

Steve McIntyre of Climate Audit did an interesting graph that shows the difference between the NH and SH using the RSS data:

Mauna Loa to improve CO2 data reporting

Regular readers may recall our conversations this week on the hiccup in CO2 data from the Mauna Loa Observatory. I’m pleased to announce that I received this encouraging email today from Dr. Pieter Tans, who is responsible for the Mauna Loa CO2 data. The data reporting will improve.

—– Original Message —–

From: “Pieter Tans” Pieter.Tans@xxxxx.xxx

To: “Anthony Watts- TVWeather” awatts@xxxxxx.xxx

Sent: Thursday, August 07, 2008 12:11 PM

Subject: Re: wrap up - again my thanks

Anthony,

I will start a change log with the next update, and the monthly file for
MLO that can be downloaded will have the number of days that went into
each month.  I will also add a description of how we actually make and
quality-control these measurements because I found a lot of
misperception about that.  These descriptions are in the scientific
literature but that’s too far removed from most people.

Pieter

Let me be the first to publicly congratulate Dr. Tans on this. On behalf of myself and others that frequent here, we sincerely appreciate this improvement in data detail and reporting. - Anthony

Strong Start Increases NOAA’s Confidence for Above-Normal Atlantic Hurricane Season

Contact: Carmeyia Gillis
FOR IMMEDIATE RELEASE

301-763-8000, ext, 7163 Aug. 7, 2008

Strong Start Increases NOAA’s Confidence for Above-Normal Atlantic Hurricane Season

In the August update to the Atlantic hurricane season outlook, NOAA’s Climate Prediction Center has increased the likelihood of an above-normal hurricane season and has raised the total number of named storms and hurricanes that may form. Forecasters attribute this adjustment to atmospheric and oceanic conditions across the Atlantic Basin that favor storm development - combined with the strong early season activity.

NOAA now projects an 85 percent probability of an above-normal season – up from 65 percent in May. The updated outlook includes a 67 percent chance of 14 to 18 named storms, of which seven to 10 are expected to become hurricanes, including three to six major hurricanes of Category 3 strength or higher on the Saffir-Simpson Scale. These ranges encompass the entire season, which ends November 30, and include the five storms that have formed thus far.

In May, the outlook called for 12 to 16 named storms, including six to nine hurricanes and two to five major hurricanes. An average Atlantic hurricane season has 11 named storms, including six hurricanes and two major hurricanes.

“Leading indicators for an above-normal season during 2008 include the continuing multi-decadal signal – atmospheric and oceanic conditions that have spawned increased hurricane activity since 1995 – and the lingering effects of La Niña,” said Gerry Bell, Ph.D., lead seasonal hurricane forecaster at NOAA’s Climate Prediction Center. “Some of these conditions include reduced wind shear, weaker trade winds, an active West African monsoon system, the winds coming off of Africa and warmer-than-average water in the Atlantic Ocean.”

Another indicator favoring an above-normal hurricane season is a very active July, the third most active since 1886. Even so, there is still a 10 percent chance of a near normal season and a five percent chance of a below normal season.

NOAA’s hurricane outlook is a general guide to the expected level of hurricane activity for the entire season. NOAA does not make seasonal landfall predictions since hurricane landfalls are largely determined by the weather patterns in place as a hurricane approaches.

Five named storms have formed already this season. Tropical Storm Arthur affected the Yucatan Peninsula in late May and early June. Bertha was a major hurricane and the longest-lived July storm (July 3-20) on record. Tropical Storm Cristobal skirted the North Carolina coastline. Dolly made landfall as a Category 2 hurricane at South Padre Island, Texas on July 25. And on August 5, Tropical Storm Edouard struck the upper Texas coast.

“It is critical that everyone know the risk for your area, and have a plan to protect yourself, your family and your property, or to evacuate if requested by local emergency managers. Be prepared throughout the remainder of the hurricane season,” Bell said. “Even people who live inland should be prepared for severe weather and flooding from a tropical storm or a hurricane.”

The Atlantic hurricane season includes activity over the Atlantic Ocean, Caribbean Sea and Gulf of Mexico. The peak months of the season are August through October.

NOAA understands and predicts changes in the Earth’s environment, from the depths of the ocean to the surface of the sun, and conserves and manages our coastal and marine resources. Visit http://www.noaa.gov

On the Web:

NOAA’s National Weather Service: http://www.weather.gov

NOAA’s Climate Prediction Center: http://www.cpc.ncep.noaa.gov

Updated 2008 Atlantic Hurricane Outlook:

http://www.cpc.ncep.noaa.gov/products/outlooks/hurricane

- 30 -

RSS July Global Temperature Anomaly - up a bit

RSS (Remote Sensing Systems of Santa Rosa, CA) RSS Microwave Sounder Unit (MSU) lower troposphere global temperature anomaly data for July 2008 was published today and has moved a bit above the zero anomaly line, with a value of 0.147°C for a positive change (∆T) of  0.112°C globally from June 2008.

RSS
2008 1 -0.070
2008 2 -0.002
2008 3   0.079
2008 4   0.080
2008 5 -0.083
2008  6  0.035
2008  7  0.147

I rather expected it to go up a bit, given that La Nina has diminsihed, plus the NH has a greater landmass than the SH, and we are in summer. But compared though to July 2007, at 0.363, it is still lower, down 0.216.

Click for larger image