By Andy May

I just gave an informal Zoom talk to a small group on measuring climate change through temperatures. The host, Dave Siegel, recorded it and has posted the presentation here, if you want to view it. It is about 15 minutes, plus some discussion afterword.

The PowerPoint slides can be downloaded here, and the slides with my notes can be downloaded here.

The key points of the talk are:

• The IPCC and I agree that temperature is a key indicator of the changing state of the climate system.
• The IPCC has traditionally used the global mean surface temperature (GMST) to estimate global temperature change, it has an organized database behind it, but atmospheric temperatures are very chaotic, so it might not be meaningful from a climate perspective.
• The new GSAT (global surface air temperature) model-based measure of warming is highly problematic, if it is introduced, as planned, in AR6. It is calculated with a model from GMST and increases the warming rate by 4%. Models suggest that GSAT is warming faster than GMST, but the data that exists does not support this extra warming. The data we have are mainly night marine air temperature measurements from ships.
• The ocean mixed layer is in constant communication with the surface and has 27x the heat capacity of the entire atmosphere. It covers 71% of Earth’s surface and does not react to short-term chaotic swings in atmospheric temperature. As a result, it is a more stable long-term record of climate change.
• The deeper ocean, below the mixed layer, is a record of temperatures in the past.
• A model is needed to build a good temperature record from current deep ocean temperatures plus proxies from ocean floor sediments.
• The phrase “climate change” is redundant, climate always has always changed and always will, we should just say “climate.”

The final slide of the presentation illustrates what can be done, it uses data from Yair Rosenthal, 2013, Science.

The left-hand graph shows a temperature reconstruction by Yair Rosenthal and colleagues in their 2013 paper in Science. They use bottom-dwelling foraminifera in the Makassar Strait, between Sulawesi and Borneo in Indonesia. The water at about 500-meters, where the forams live, is sourced from the Southern Ocean near Antarctica, the southern Indian Ocean and the North Pacific. This location is ideal for checking the 500-meter water temperature for much of the Southern Hemisphere and a portion of the Northern Hemisphere.

Deeper water is more insulated from the surface and the trends reflect longer-term climatic changes, uncontaminated with atmospheric variability.

On the right we see a location map and a temperature profile for the Makassar Strait from the University of Hamburg database. The database is a high resolution (0.25° latitude and longitude) monthly series that uses all available data from many years. This profile gets most of its data from 2004-2016. It shows an average temperature, at 500 meters, of about 7.7°C. Thus, this area, at 500 m, warms about 0.5°C from the depths of the Little Ice Age. Here the low temperature was 7.2°C in 1810.

The Holocene Climatic Optimum is identified on the graph, and in this strait, the temperature was often over 10 degrees, the Medieval Warm Period was about 8.5°C, much warmer than today.

In summary, the data we need to reconstruct Holocene, and older temperatures are in the oceans and in ocean sediments. Ocean temperature reconstructions represent much more of Earth’s surface (defined as from the ocean floor to the top of the atmosphere) than any land- or ocean-based measurements in the atmosphere. The atmosphere is too chaotic and unstable to give us representative climatic trends. Ocean temperatures are more stable, usable, and easier to compare to paleo-temperatures.

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March 26, 2021 at 05:03PM

Among its top search results today for “climate change,” Google News is highlighting an article from Defense News titled, “Battling climate change starts with military action.” The article falsely claims climate change is threatening U.S. military operations and preparedness by enhancing sea level rise and extreme weather events. Both claims are untrue. Data from the United Nations Intergovernmental Panel on Climate Change (IPCC) and from the U.S. National Oceanic and Atmospheric Administration (NOAA) consistently show the number and intensity of extreme weather events, from hurricanes to wildfires are about the same, or even slightly less frequent and severe, than they have been historically.

Cmdr. Benjamin Simon writes:

“The effects of climate change are all around. They can be seen by the Gulf Coast bracing for seven named storms in 2020; wildfires in California interrupting electricity for hundreds of thousands ….

As a 16-year naval aviator, I have seen how serious climate instability is: From the flooding of our naval bases, due to the rising sea level, to increased storms at a higher intensity, the climate emergency is affecting our military’s capability to operate. During my service, I had to cancel missions due to hurricanes, typhoons and other severe weather.”

It is almost certainly true that during his career as a naval aviator Simon has had to cancel missions due to extreme weather. He has also likely seen military bases flood on occasion. However, hurricanes and flooding are historically common natural occurrences, long pre-dating the current obsession with climate change. Also the best available evidence indicates such extremes are not becoming more common, nor is the current rate of sea level rise exceeding historic rates.

As discussed in Climate Realism here, here, and here, for example, 2020 did not a set a record for hurricanes in the United States, and hurricane numbers and intensity have been in a long-term decline (See the figure below).

Simon presents no evidence California’s 2020 wildfire season disrupted any military operations. However, even if it did, as discussed here and here, for example, there is copious evidence wildfires across the Western United States have been in a long-term decline. Also historically, California has experienced wildfire seasons as bad as, or worse than, 2020’s on a nearly annual basis.

Sea levels are rising. However, as detailed in Climate at a Glance: Sea Level Rise: Data shows global sea level has been rising at a relatively steady pace of approximately one foot per century since at least the mid-1800s, which was long before coal power plants and SUVs. Moreover, the United Nations Intergovernmental Panel on Climate Change (IPCC) confirms here has been no significant recent acceleration.

Global sea level has risen approximately 400 feet since the beginning of the end of the most recent ice age—approximately 20,000 years ago. The rate of sea level rise has risen and fallen at various times since then, slowing and increasing on the order of tens, hundreds, and thousands of years over the past 20,000 years. None of this variance had anything to do with human activities. Indeed, as NASA reports, sea level always rises between ice ages as ice sheets retreat. During the last interglacial period between ice ages, seas were four to six meters higher than we are experiencing today.

As shown in Climate Realism recent claims made by climate alarmists that sea level rise has been accelerating is due to scientists combining the two dissimilar data sets from different sets of satellites, neither of which shows accelerated sea level rise. They then plotted a new trend showing acceleration. As meteorologist Anthony Watts writes concerning this manipulation of the data, “This is either incompetent or dishonest, and certainly not up to even the simplest of basic science principles.”

Recent flooding at naval stations, as is true for many cities around the world, is due more to land subsidence—the gradual sinking of land either under its own weight, under the weight of manmade structures, due to water withdrawals from aquifers, and from the conversion and replacement of wetlands with infrastructure—rather than from sea levels rising at an increasing rate. As noted in a report by the National Center for Public Policy Research:

In a 2010 report submitted to the U.S. Army Corps of Engineers, the Virginia Institute of Marine Science found that 50 percent of the relative sea-level rise at Chesapeake Bay water-level stations between 1976 and 2007 was due to subsidence. At Norfolk and other bases subject to subsidence, it’s not just the seas that are rising, but the land that’s sinking.

In order for climate change to be hampering U.S. military operations and preparedness, it must first be causing more frequent or severe weather events or making seas rise faster. Data demonstrates it is not, and Google News and Defense News should know this.

The post No Defense News, Climate Change Can’t Be Threatening Military Operations if Weather Isn’t Getting Worse appeared first on Climate Realism.

via Climate Realism

By H. Sterling Burnett -March 25, 2021

No, Defense News, Climate Change Can’t Be Threatening Military Operations if Weather Isn’t Getting Worse

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