By Philip Klotzbach and William M. Gray
We have lowered our seasonal forecast slightly; however, we continue to call for a very active Atlantic basin hurricane season in 2007. We expect 13 named storms, 8 hurricanes and 4 intense hurricanes (CAT 3-5). Landfall probabilities for the United States coastline remain above their long-period averages - Entire U.S. coastline - 68% (average for last century is 52%), U.S. East Coast Including Peninsula Florida - 43% (average for last century is 31%) and the Gulf Coast from the Florida Panhandle westward to Brownsville - 44% (average for last century is 30%). Read full detailed analysis here.
By Dr. Anthony Lupo, University of Missouri
Recently, there has been a lot written about changes in hurricane frequency and how these changes may be an indicator of climate change. Yet another study has been released indicating that human activity may be partly responsible for the rise in hurricane activity over the course of the 20th century. The latest is a study entitled, ”Heightened Tropical Cyclone Activity in the North Atlantic: Natural Variability or Climate Trend?”, and published in the Philosophical Transactions of the Royal Society of London.
However, there are a few problems with the conclusions of the authors. The first and most important is that observation practices have changed radically since the 1900 – 1930 period. Today we have satellites watching over the oceans for hurricane formation. Satellite records have also allowed us to go back and “pick-up” storms that may have been missed previously and add them to the record. Naturally, there should be more tropical storms in the last few years than in the period before 1930. Also, in the most recent decades, the National Hurricane Center has named hurricanes and tropical storms, but also what they call “subtropical storms”. These storms are hybrids which have many characteristics of both tropical storms and non-tropical storms.
The problem described is akin to the change in tornado frequencies since 1900. During the 1920’s, the US averaged roughly 100 tornadoes per year, while during the last few decades, the mean has been closer to 1200. No one would argue that this 10-fold increase in tornado counts is due, even in part, to climate change.
Read full story here.
By CO2 Science
In the 24 March 2006 issue of Science, a number of commentaries heralded accelerating discharges of glacial ice from Greenland and Antarctica, while dispensing dire warnings of an imminent large, rapid and accelerating sea-level rise (Bindschadler, 2006; Joughin, 2006; Kerr, 2006; Kennedy and Hanson, 2006). This distressing news was based largely on three reports published in the same issue (Ekstrom et al., 2006; Otto-Bliesner et al., 2006; Overpeck et al., 2006), wherein the unnerving phenomena were attributed to anthropogenic-induced global warming, which is widely claimed to be due primarily to increases in the air’s CO2 content that are believed to be driven by the burning of ever increasing quantities of fossil fuels such as coal, gas and oil. But does all of this make any sense?
Hanna and Cappelen (2003) determined the air temperature history of coastal southern Greenland from 1958-2001, based on data from eight Danish Meteorological Institute stations in coastal and near-coastal southern Greenland, as well as the concomitant sea surface temperature (SST) history of the Labrador Sea off southwest Greenland, based on three previously published and subsequently extended SST data sets (Parker et al., 1995; Rayner et al., 1996; Kalnay et al., 1996). Their analyses revealed that the coastal temperature data showed a cooling of 1.29°C over the period of study, while two of the three SST databases also depicted cooling: by 0.44°C in one case and by 0.80°C in the other. In addition, it was determined that the cooling was “significantly inversely correlated with an increased phase of the North Atlantic Oscillation over the past few decades.”
Read full detailed analysis here.
By Roger Pielke Sr. Climate Science Blog
In a posting on July 26, Roger commented on the backtracking of Kevin Trenberth in a second posting on the Nature weblog.
Kevin Trenberth has followed up his weblog on the Nature site Climate Feedback - The Climate Change Blog entitled “Predictions of climate” with a weblog on the subject of climate prediction. This new posting is entitled ”Global Warming and Forecasts of Climate Change.”
Unfortunately, this new post lacks the candor that is in the original Nature weblog by Kevin Trenberth on this subject (as discussed on Climate Science here).
It should be clear in his new Nature weblog that, unfortunately, his candid comments in this earlier weblog resulted in negative feedback from his colleagues such that he felt compelled to follow up with a poor summary of climate forecasting. This is unfortunate, as his original weblog was a bridge that can be used to advance climate science.
By Dr. Bill Gray in WSJ Online
Some scientists, journalists and activists see a direct link between the post-1995 upswing in Atlantic hurricanes and global warming brought on by human-induced greenhouse gas increases. This belief, however, is unsupported by long-term Atlantic and global observations.
Consider, for example, the intensity of U.S. land-falling hurricanes over time—keeping in mind that the periods must be long enough to reveal long-term trends. During the most recent 50-year period, 1957 to 2006, 83 hurricanes hit the United States, 34 of them major. In contrast, during the 50-year period from 1900 to 1949, 101 hurricanes (22% more) made U.S. landfall, including 39 (or 15% more) major hurricanes.
If global warming isn’t the cause of the increased Atlantic hurricane activity seen over the past dozen years, what is? My Colorado State University colleagues and I attribute the increase in hurricane activity to the speed-up of water circulating in the Atlantic Ocean. This circulation began to strengthen in 1995—at exactly the same time that Atlantic hurricane activity showed a large upswing.
See full story here.
By Craig Woods, WOOD TV8 Blog
The June issue of the Bulletin of the American Meteorological Society (a peer-reviewed journal) has a couple of interesting articles about the climate network here in the United States. I am posting these articles not to claim that warming has not occurred, because it has, but to shed further light on how much uncertainty there is not only in the data but in the future of the network itself. Roger Pielke Sr. from The University of Colorado at Boulder, along with 14 other coauthors has an article titled: Documentation of Uncertainties and Biases Associated with Surface Temperature Measurement Sites for Climate Change Assessment. The conclusion of the authors’ analysis is: “…there are large uncertainties associated with the surface temperature trends from the poorly sited stations. Moreover, rather than providing additional independent information, the use of the data from poorly sited stations provides a false sense of confidence in the robustness of the surface temperature trend assessments.”
USHCN Station Hopkingsville, KY
Read more on this story and another on problems with the precipitation measurement network as well as an open letter to congress from the American Association of State Climatologists about the slow collapse of the 116 year climate observing network on Craig’s blog here.
By Sherwood, Keith and Craig Idso
Climate alarmists are always talking about abrupt climate changes resulting from earth’s rising temperature passing some ominous “tipping point” that triggers the occurrence of more numerous and severe storms, floods and droughts. One need only look to Al Gore’s testimony of 21 March 2007 before the United States Senate’s Environment and Public Works Committee for confirmation of this fact, wherein he states - without equivocation - that “droughts are becoming longer and more intense,” but, of course, without offering any evidence in support of his contention.
To fill this gaping void with respect to drought, we here report the findings of Narisma et al. (2007), who analyzed “global historical rainfall observations to detect regions that have undergone large, sudden decreases in rainfall [that] are statistically significant at the 99% level, are persistent for at least ten years, and .. have magnitudes that are [mostly] 10% lower than the climatological normal (1901-2000 rainfall average).”
With respect to the temporal distribution of the 30 severe and persistent droughts identified by Narisma et al., seven of them occurred during the first two decades of the 20th century (1901-1920), seven occurred during the next two decades (1921-1940), eight during the middle two decades of the century (1941-1960), but only five during the next two decades (1961-1980), and a mere three during the final two decades of the century (1981-2000), which is not at all what one would have expected if the climate-alarmist thesis that is propounded by Gore and his followers was correct.
Read the full review here.
By Lawrence Solomon, Financial Post
Paleoclimate scientist Bob Carter:
“The accepted global average temperature statistics used by the Intergovernmental Panel on Climate Change show that no ground-based warming has occurred since 1998. Oddly, this eight-year-long temperature stasis has occurred despite an increase over the same period of 15 parts per million (or 4%) in atmospheric carbon dioxide. “Second, lower-atmosphere satellite-based temperature measurements, if corrected for non-greenhouse influences such as El Nino events and large volcanic eruptions, show little, if any, global warming since 1979, a period over which atmospheric CO2 has increased by 55 ppm (17%).”
One of the most contentious areas of climate-change science involves computer General Circulation Models (GCMs), the predictive tool that generate most of the scary scenarios that arouse public alarm. Prof. Carter has long been a critic of these models, which claim to project for us what the climate will be in the year 2100.
In the past, Prof. Carter has drawn the ire of global-warming proponents with his GCM critiques. Now, to his satisfaction, he has support in his critique from an unlikely source—Kevin Trenberth, whom he thinks of as “one of the advisory high priests of the UN’s Intergovernmental Panel on Climate Change.”
As Dr. Trenberth recently acknowledged to Nature journal’s Climate Feedback blog, IPCC models cannot predict future climate because they don’t reflect reality: “None of the models used by IPCC are initialized to the observed state and none of the climate states in the models correspond even remotely to the current observed climate,” he stated.
Read more here.