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Sea Level Long-Term History

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Researchers discover a new tool for reconstructing ancient sea ice – Watts Up With That? Research News PROVIDENCE, R.I. [Brown University] — Sea ice is a critical indicator of changes in the Earth’s climate. A new discovery by Brown University researchers could provide scientists a new way to reconstruct sea ice abundance and distribution information from the ancient past, which could aid in understanding human-induced climate change happening now. In a study published in Nature Communications, the researchers show that an organic molecule often found in high-latitude ocean sediments, known as tetra-unsaturated alkenone (C37:4), is produced by one or more previously unknown species of ice-dwelling algae.

As sea ice concentration ebbs and flows, so do the algae associated with it, as well as the molecules they leave behind. “We’ve shown that this molecule is a strong proxy for sea ice concentration,” said Karen Wang, a Ph.D. student at Brown and lead author of the research. Other types of alkenone molecules have been used for years as proxies for sea surface temperature. Holocene Thermal Optimum and Sea Level.

Sea Level in the Middle Ages

History falsifies climate alarmist sea level claims | Watts Up With That? Seas have been rising and falling for thousands of years – without help from the EPA or IPCC Guest essay by Robert W. Endlich Sea levels are rising rapidly! Coastal communities are becoming more vulnerable to storms and storm surges! Small island nations are going to disappear beneath the waves!

Climate alarmists have been making these claims for years, trying to tie them to events like “Superstorm” Sandy, which was below Category 1 hurricane strength when it struck New York City in October 2012, and Typhoon Haiyan, which plowed into the low-lying central Philippines in November 2013. For alarmists, it does not seem to matter that the strength and frequency of tropical storms have been decreasing in recent years, while the rate of sea level rise has fallen to about seven inches per century. The alarmist cries are not meant to be honest or factual. China is rapidly becoming one of the richest nations on Earth. The facts of history are clear. Robert W. Like this: Like Loading... 70+ scientific papers say: Today’s Sea Level Change Indistinguishable From Noise. Holocene Sea Levels were 2 Meters Higher 1. Are Modern ‘Anthropogenic’ Sea Levels Rising At An Unprecedented Rate?

No. Despite the surge in CO2 concentrations since 1900, the UN’s Intergovernmental Panel on Climate Change (IPCC) has concluded that global sea levels only rose by an average of 1.7 mm/yr during the entire 1901-2010 period, which is a rate of just 0.17 of a meter per century. During the 1958 to 2014 period, when CO2 emissions rose dramatically, a recent analysis revealed that the rate of sea level rise slowed to between 1.3 mm/yr to 1.5 mm/yr, or just 0.14 of a meter per century. Frederiske et al.,2018 “Anthropogenic” Global Sea Level Rise Rate (1958-2014): +0.14 of a meter per century “For the first time, it is shown that for most basins the reconstructed sea level trend and acceleration can be explained by the sum of contributors, as well as a large part of the decadal variability. 2. ~15,000 – 11,000 Years Ago, Sea Levels Rose At Rates Of +4 to +6 Meters Per Century 3. Cartology Affirms Relative Sea Levels Were The Same Or HIGHER Than Now During The Little Ice Age.

Surprisingly accurate nautical maps created the 17th to 19th centuries strongly suggest coastal land area in both hemispheres were quite similar to today’s. There is even evidence relative sea levels were higher than now back then. Image Source: Globally, coasts have grown since the 1980s Between 1985 and 2015, satellite observations indicate the world’s coasts gained 13,565 km² more land area than they had lost to the seas (Donchyts et al., 2016). This means more coastal land area is above sea level today than in the 1980s. This surprises scientists, as they “expected the coast would start to retreat due to sea level rise,” but instead they observed “coasts are growing all over the world.” Image Source(s): Donchyts et al., 2016 and BBC (press release) These recent trends would appear to be the opposite of what would be expected with modern global warming.

Are relative sea levels lower now than during the 1800s? 1. Image Source: Antique Maps Online 2. Image Source: 3. 4. Historical European Sea Level Records. Guest Essay by Kip Hansen I have been working on another sea level related essay and in the process stumbled upon a paper published in 1990 by the Permanent Service for Mean Sea Level (PSMSL). The title is: “On The Availability Of European Mean Sea Level Data by P.L. Woodworth, N.E. Spencer and G. I am not going to comment on the data itself, other than to include the PSMSL caveat that accompanies other papers of the late 1980s. Here are the graphs from the cited paper: I would be remiss if I did not include the caveat that PSMSL adds to papers of this period (1980s — early 1990s): What I see in the above is that Stockholm, an obvious outlier, has a strong downward trend — this is to be expected as Stockholm is in an area of positive (upward) Vertical Land Movement.

I post these graphs for the sole purpose of bringing them into the current century where they can be seen and taken into account. 2. Relative sea level is where the sea surface hits the land. 3. 4. 5. 6. 7. Author’s Comment: CO2 Control Knob? A 15-22°C Warmer Arctic With Sea Levels 25 m Higher When CO2 Ranged From 300-400 ppm. CO2 concentrations have risen from 310 ppm to 410 ppm since the 1930s. However, there has been no net change in Arctic or Greenland temperatures during these last 90 years.

During the Pliocene, CO2 also ranged between about 300-400 ppm, but the Arctic was 15-22°C warmer and sea levels 25 meters higher than today. Is CO2 really Earth’s “control knob”? Nearly ten years ago, the imagery of a CO2 “control knob” for climate was canonized in the journal Science. Image Source: Lacis et al., 2010 The CO2 concentration was said to determine – or control – Earth’s temperature. However, the scientific literature’s paleoclimate record does not provide fundamental support for this paradigm of a CO2-controlled climate. During the Ordovician, for example, CO2 concentrations reached 4,200 ppm – more than 10 times today’s levels.

Image Source: Shuang et al., 2019 Arctic/Greenland warming? Image Source: Araźny et al., 2019 Image Source: Hanhijarvi et al., 2013 Image Source: Hanna et al., 2011. New Study Shows Sea Level Near In Western Pacific Was 0.4 Meters Higher 3600 Years Ago Than Today. Alarmists say that sea levels are rising rapidly, and unless we act now to take over the climate using the secret man-made CO2 reduction method, soon New York and even Cologne, Germany, will end up in water.

At least that’s the alarmist scenario that the Truth Media like to tell us about. However, a number of studies and tide gauge data tell us a very different story. Hat-tip: reader Mary Brown. The latest study titled: Holocene sea-level change and evolution of a mixed coral reef and mangrove system at Iriomote Island, southwest Japan, by Yamano et al tells us that sea levels were more than 1 meter higher 5100 to 3600 years ago than they are today they, or 0.4 meters when corrected for tectonics. The paper’s abstract follows: Exposed fossil microatolls and core samples from a coral reef and a mangrove forest at the Yutsun River mouth, Iriomote Island, southwest Japan, reveal the internal structure and temporal changes in the sedimentary processes of a mixed reef–mangrove system. Sea level change in the Middle Ages and the Little Ice Age (LIA) Figuur 2.3. De gemiddelde hoogwater kromme voor de zuidelijke Noordzee (naar Jensen e.a.,1993) en de gemiddelde wereldtemperatuur (volgens Barth & Titus,1984 ) over de laatste 1000 jaar illustreert dat stijging en daling van de mondiale temperatuur samengaat met stijging en daling van het gemiddeld hoogwater (HW).

________________________________________________________________________________________________________________________Behre, 2003 , Behre, 2007 (German North Sea coast, German Bight): Behre, 2004, Abb. 2 (German North Sea coast): Abb. 3: Meeresspiegel an der südlichen Nordseeküste (aus K. -E. See also the critical comments on Behre's sea level curve for the southern North Sea (2003, 2004, 2007) by Baeteman, Waller and Kiden (2011) and Bungenstock and Weerts (2010, 2012), and Behre's response (2012). North Sea coast of the Netherlands and Belgium Relative sea level rise during the Holocene along the North Sea coast (TNO-NITG, 2003). Grinsted et al., 2009 (Global Sea Level): Relative sea-level change in Newfoundland, Canada during the past ∼3000 years.

No. Doggerland is not a relevant climate change lesson from a “real Atlantis.” Temperatures, Sea Levels ‘Naturally’ Rise 30 – 40 Times Faster Than Today’s Rates. By Kenneth Richard on 13. April 2017 Modern Temperatures Only Rising 0.05°C/Decade Since 1850, CO2 concentrations have risen from 285 ppm to 400 ppm. During these ~165 years, the IPCC has concluded that surface temperatures have warmed by 0.78°C. This is a warming rate of only 0.05°C per decade for 1850-2012 — which happens to be the same rate of warming over the 1998-2012 period.

IPCC AR5 (2013): “The globally averaged combined land and ocean surface temperature data as calculated by a linear trend, show a warming of 0.85°C over the period 1880 to 2012, when multiple independently produced datasets exist. The total increase between the average of the 1850–1900 period and the 2003–2012 period is 0.78 °C, based on the single longest dataset available 4 (see Figure SPM.1). … [T]he rate of warming over the past 15 years (1998–2012; 0.05 °C per decade), which begins with a strong El Niño, is smaller than the rate calculated since 1951 (1951–2012; 0.12 °C per decade).” Sánchez et al., 2017. Sea Level Decline Over The Past 1,700 Years | The Deplorable Climate Science Blog. A Historic Perspective on the Greenland Ice Sheet and its Contribution to Global Sea Level. Paper Reviewed Vasskog, K., Langebroek, P.M., Andrews, J.T., Nilsen, J.E.Ø. and Nesje, A. 2015.

The Greenland Ice Sheet during the last glacial cycle: Current ice loss and contribution to sea-level rise from a palaeoclimatic perspective. Earth-Science Reviews 150: 45-67. One of the most feared of all model-based projections of CO2-induced global warming is that temperatures will rise to such a degree as to cause a disastrous melting/destabilization of the Greenland Ice Sheet (GrIS), which melting is subsequently projected to raise global sea level by several meters. But how likely is this scenario to occur? And is there any way to prove such melting is caused by human activities? The answer to this two-part question involves some extremely complex and precise data collection and understanding of the processes involved with glacial growth and decay.