The USGCRP has just released another report that has been trumpeted by the mainstream media as showing that increased risk and peril are upon us. According to report, “The Climate Science Special Report (CSSR) … provides a detailed analysis of how climate change is affecting the physical earth system across the United States.”
The report is long on a scary narrative but short on clear supporting factual data. It claims the “Earth’s climate is now changing faster than at any point in the history of modern civilization, primarily as a result of human activities. The impacts of global climate change are already being felt in the United States and are projected to intensify in the future.”
If we are to believe this narrative, temperatures are climbing at an unprecedented rate, hurricanes are becoming more severe, and sea level rise is increasing and represents a greater threat to coastal areas–all of which represent an unprecedented risk. Dr. Roy Spencer, one of the developers of our satellite measurement system, regularly publishes a global temperature update. The following chart shows that average temperatures for the past two decades are not rising. The evidence of the post 1998 pause is clearly evident.
There is also a contention that hurricanes are increasing in intensity and frequency. NOAA’s Hurricane Data Center publishes hurricane data as far back as 1850. These data completely contradict the report’s assertions. Looking at the actual data brings to mind, Groucho Marx’s question, “are you going to believe your lying eyes or what I tell you.” The claim is made that Hurricane Michael is an indicator of what to expect in the future because of the warming waters in the Gulf of Mexico. But here again, the data contradict the narrative. The Gulf’s temperature at the time of Michael was not especially warm nor unusual. The average Gulf temperature can vary by + or – 5 to 7 degrees in the September to October time period. Roy Spencer also recently pointed out that 7 of the warmest Gulf years since 1860 took place before 1970.
With so much coastal development, there is legitimate concern about the rise in sea level. The report claims that since 1993 sea level has been rising at twice the 0.05 inch per year during the 20th century. But this assertion is contradicted by Figure 3-14 in the IPCC’s recent AR-5 report
Left unsaid are some embarrassing facts. Sea level has been rising for the past 16,000 years, the end of the last ice age. Every reputable oceanographer admits that it will continue to rise until the next one. The impact of human caused warming is on top of the natural rise that has been taking place. While advocates provide what appear to be precise measurements of sea level rise, they are just guessing because we lacked reasonably precise measurements before 1993. Even though satellite measurements are more precise they still require adjustments for atmospheric water vapor, orbits tides, and wave height biases, among other factors that can impact their accuracy. There is also the effect of subsidence.
The Special Report calls for urgent action to avoid the serious consequences of climate change and the action called for is the reduction in CO2 emissions. Unfortunately for the authors, they conveniently overlooked the fact that US CO2 emissions peaked in 2007 and have been on a downward trajectory since then. The reduction in emissions is even more impressive given the fact that population has grown 9% and the economy more than 40%. The USGCRP would better serve the interests of the nation if it focused on reducing important uncertainties in our understanding of the climate system and in improving both data quality and the models that use the data.