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Sea Level Rise Not Accelerating, New Study Shows

June 7, 2019

Climate Change Weekly #325

A new report by Drs. Craig Idso, David Legates, and S. Fred Singer, released by The Heartland Institute, shows the Intergovernmental Panel on Climate Change (IPCC) and other government and nongovernment organizations are wrong to claim sea levels are increasing at an unusually rapid rate due to anthropogenic climate change. The scientists analyzed peer-reviewed literature examining long-term data from tidal gauges and other sources and found the amount of sea level increase the Earth has experienced over the past century is not unusual historically, nor has the rate of rise increased significantly over the past few decades.

Though the amount and rate of sea level rise has varied considerably at different locations over varying time periods due to factors such as land subsidence, land rebound or emergence, erosion, and other localized factors, on average global sea levels have risen approximately 400 feet since the beginning of the end of the most recent ice age approximately 20,000 years ago.

Many government researchers, anti-fossil-fuel activists, and the mainstream media parrot IPCC Working Group I’s assertion it is “very likely” sea level rise has accelerated since the middle of the twentieth century in response to warming caused by rising greenhouse gas emissions and “it is very likely that the rate of global mean sea level rise during the 21st century will exceed the rate observed during 1971–2010 … due to increases in ocean warming and loss of mass from glaciers and ice sheets.”

In truth, while seas have risen a great deal since the end of the last ice age, the rate of sea level rise has risen and fallen, slowing and increasing on the order of tens, hundreds, and thousands of years over the last 20,000 years, having nothing whatsoever to do with human activities. More recently, as Heartland’s study reports, “the highest quality coastal tide gauges from around the world show no evidence of acceleration since the 1920s.”

The report points out there is a disconnect between data recorded by the global tidal gauge system and other coastal data sources, and projections made by IPCC. According to the authors, the discrepancy arises because

Like ice melting, sea-level rise is a research area that has recently come to be dominated by computer models. Whereas researchers working with datasets built from long-term coastal tide gauges typically report a slow linear rate of sea-level rise, computer modelers assume a significant anthropogenic forcing and tune their models to find or predict an acceleration of the rate of rise.

One comprehensive paper cited in Heartland’s new report examined six different data sets accounting for hundreds of tidal gauges with lengthy existences and found “all consistently show a small sea-level rate of rise and a negligible acceleration.”

A 2017 report released by The Heartland Institute, by geophysicist Dennis Hedke, analyzed data collected from ten coastal cities with relatively long and reliable sea-level records, including Ceuta, Spain; Honolulu, Hawaii; Atlantic City, New Jersey; Sitka, Alaska; Port Isabel, Texas; St. Petersburg, Florida; Fernandina Beach, Florida; Mumbai/Bombay, India; Sydney, Australia; and Slipshavn, Denmark. Hedke found there was no correlation between changes in sea levels at these locations and rising carbon dioxide levels.

For some cities, the rate of sea level rise has remained virtually constant, neither increasing nor declining appreciably from the rates experienced before humans began adding substantial amounts of greenhouse gases to the atmosphere. By contrast, some cities, like Ceuta, Spain, have experienced very little sea level rise over the past century, exhibiting almost a flat trend line, below the historic rate of global sea level rise of approximately seven inches per century. Other cities, such as Sitka, Alaska have actually experienced falling sea levels. Still other cities, such as Atlantic City, have experienced a large, rapid increase in sea levels.

The point is, different areas around the world are having different experiences with sea levels, none of which correspond well either with the projections made by IPCC based on computer models or the steady increase in atmospheric greenhouse gas concentrations. Rather than responding to rising greenhouse gas levels, changes in sea levels seem to reflect localized conditions.

As climatologist David Legates of the University of Delaware testified at a February 7 hearing on “Coastal Hazards” before the U.S. House Natural Resources Committee’s Subcommittee on Water, Oceans, and Wildlife,

Coasts are naturally hazardous areas due to the impact of rising seas, coastal storms, shifting barrier islands, and flooding caused by rainfall into low-lying areas. Global sea levels have risen naturally at a rate of about 7 to 8 inches per century for at least several hundred years. Locally, this rate may be higher due to local land subsidence and/or compaction of sediments or lower due to isostatic rebound.

[I]ncreasing CO2 concentrations are not significantly affecting the rate of sea level rise. As these concentrations have increased from before the industrial age when atmospheric CO2 levels were about 280 ppm to current conditions where they exceed 400 ppm, the lack of a significant change in the rate of increase implies that sea level rise is not responding to changes in greenhouse gas concentrations.

Human activities, such as the construction of barriers, the channelization of rivers, installing pumps, the conversion of coastal wetlands to densely populated metropolitan areas, filling in shallow water bays, replenishing eroded beaches, and the draining of coastal aquifers for human consumption, have undoubtedly contributed to making coastal regions and populations both more and less vulnerable to rising seas, depending on the location and the human intervention undertaken. However, when analyzing the causes and consequences of changing sea levels, there is little actual evidence human-caused climate change is contributing to higher ocean levels.

  • H. Sterling Burnett

SOURCES: The Heartland Institute; The Heartland Institute; congressional testimony


Setting the record straight on methane emissionsAs government support wanes in Europe, so does green energy … China cheats on CFCs


A new study published in the journal Geophysical Research Letters (GRL) shows that over the past decade, methane emissions from natural gas and oil production are as much as “an order of magnitude lower” than previous studies claimed.

The study, from researchers at the National Oceanic and Atmospheric Administration and the University of Colorado, reports,

Based on long-term and well-calibrated measurements, we find that (i) there is no large increase of total methane emissions in the United States in the past decade; (ii) there is a modest increase in oil and gas methane emissions, but this increase is much lower than some previous studies suggest; and (iii) the assumption of a time-constant relationship between methane and ethane emissions has resulted in major overestimation of an oil and gas emissions trend in some previous studies.

The U.S. Environmental Protection Agency’s (EPA) 2018 Greenhouse Gas Inventory, released in April 2019, seems to confirm the GRL study’s findings. EPA found methane emissions have declined by 15.8 percent overall since 1990, with emissions from petroleum and natural gas systems falling by 10.5 percent and 14.2 percent, respectively, even as U.S. oil production grew by 80 percent and natural gas production increased 51 percent over the same period.

SOURCES: The Heartland Institute; Geophysical Research Letters


Renewable energy advocates have claimed in recent years wind and solar power are more than competitive with traditional sources of electric power, including coal and nuclear power, even going so far as to claim they are cheaper. Recent evidence from Europe refutes these claims once again.

A new study out of the United Kingdom reports as government support for renewable power has begun to decline, wind and solar materials production and installations have dropped sharply.

“Prospect, the union which covers much of the sector, has found a 30 percent drop in renewable energy jobs between 2014 and 2017, as government cuts to incentives and support schemes started to bite. It also found investment in renewables in the UK more than halved between 2015 and 2017,” reports the Guardian.

The sharp drop in jobs related to green energy came after the UK government, citing the rapidly falling costs of renewable energy, virtually ended programs supporting homeowners and businesses installing rooftop solar panels and stopped subsidizing onshore wind installations.

It’s not just in the UK that wind and solar power’s fortunes are waning as government support for green power ends. The Global Warming Policy Forum reports German wind turbine manufacturer Senvion S.A., which had installed more than 1,000 wind turbines across Europe in recent years, filed for insolvency in April 2019, reflecting the fact the market for its turbines had collapsed. GWPF suggests other green energy companies may soon follow Senvion into bankruptcy, as government support across Europe wanes and previously unanticipated problems with the technologies become apparent.

GWPF reports the number of new wind and solar installations across the 28 European Union nations has fallen by 50 percent since 2010 and many turbines, installed just a few years ago, are already being taken offline for repair or replacement. GWPF writes,

Having received regulatory approval, the Danish mega-developer Orsted is about to start removing and renovating all 324 blades on the 108-turbine, 389 MW, Duddon Sands wind farm in the UK part of the Irish Sea, a year after problems first became apparent. The machines … have suffered leading edge erosion, a problem that affects perhaps some 500 turbines in Europe, … and requiring the application of a remedial covering to each blade.

The Duddon Sands wind farm only began operating in 2014, and now the entire operation is being shut down for a complete makeover.

Gee, if only someone could have predicted saltwater might corrode metal at sea.

SOURCES: Global Warming Policy Forum; The Guardian


A potent greenhouse gas, CFC-11, the use of which has been banned around the globe for the last 30 years, is on the rise, and all signs point to China as the main culprit behind the increase, according to a recent study published in the journal Nature.

The 1989 Montreal Protocol on Substances That Deplete the Ozone Layer was ratified by 197 nations in an effort to prevent the thinning of the ozone layer, by halting the production and use of chlorofluorocarbons (CFC), chemicals then in common use as coolants and insulators in aerosols, foams, and refrigerants, which break down ozone.

Despite the ban, in 2018, scientists from the National Oceanic and Atmospheric Administration found global emissions of trichlorofluoromethane (CFC-11), a greenhouse gas with approximately 5,000 times more heat-trapping potential than carbon dioxide on a molecule by molecule basis, have been increasing since 2013, meaning one or more countries were secretly violating the Montreal Protocol.

Using an international network of monitors designed to identify and track gases in the atmosphere, scientists at the University of Bristol, Kyungpook National University, and the Massachusetts Institute of Technology found between 40 and 60 per cent of total global CFC-11 emissions originate from eastern China. Because the locations of monitoring stations are limited, the researchers have thus far been unable determine the source of the remaining CFC-11 emissions.

“‘It wasn’t entirely a surprise,’ said Matthew Rigby, lead author of the study and Reader in Atmospheric Chemistry in the School of Chemistry at the University of Bristol. A few months after the initial report was released last year, both the Environmental Investigation Agency and the New York Times published reports in which Chinese manufacturers in the region confirmed they were using CFC-11 in the production of foams,” reports the National Post.

The new study concludes manufacturers in eastern China alone had emitted approximately 7,000 tons of CFC-11 since 2013.

SOURCES: National Post; Nature (behind paywall)

H. Sterling Burnett, Ph.D. is a Heartland senior fellow on environmental policy and the managing editor of Environment & Climate News.