Long-term observations at the Geodynamic Observatory Moxa: Can we identify evidence for climate change?

Longterm geophysical recordings of natural Earth&#8217;s parameters besides other signals also may contain past and ongoing temperature fluctuations, as they are occurring e.g. when groundwater moves or when climate changes. Similarly, repeated logs or continuous recordings reveal the amount of ongoing climate fluctuations. However, such thermal signals in the subsurface also may have other causes, e.g. groundwater motion or fluid infiltration after strong rainfall events. The Geodynamic Observatory Moxa of the Friedrich-Schiller University Jena, Germany, is an ideal test site for long-term monitoring of the subsurface temperature distribution in boreholes using optical fibre temperature-sensing, as it is equipped with a variety of complementary sensors.A 100 m deep borehole on the ground of the Observatory, is equipped with an optical fibre and a water level gauge. Clearly shown in the records of the first five years of continuous recordings are seasonal temperature fluctuations. Seasonal fluctuations could be identified down to a depth of about 20 m and diurnal temperature signals down to 1.2 m. Precipitation events may influence subsurface temperature still in a depth as deep as 15 m. Besides these, temperature anomalies were detected at two depths, 20 m and 77 m below the surface. These anomalies most probably result from enhanced groundwater flow in aquifers. Recordings of deformation from laser strain meter systems installed in a gallery at Moxa, which are highly sensitive to pore pressure fluctuations, and measuring the physical properties during drilling the borehole, help to identify and quantify the causes of the observed&#160; temperature fluctuations.For more than 20 years variations of the Earth&#8217;s gravity field have been observed at the Observatory Moxa employing the superconducting gravimeter CD-034. Besides the free oscillations of the Earth and hydrological effects, the tides of the solid Earth are the strongest signals found in the time series. Tidal analysis of the main constituents leads to obtaining the indirect effect for all tidal waves which is mainly controlled by the loading effect of the oceans. Satellite altimetry revealed a mean global sea level rise of about 3.3 mm/a which may be caused amongst others mainly by ice melting processes in the polar regions. However, more detailed analyses and resulting global maps show that the sea level rise is not uniformly distributed over all oceans. This means that actual and future tidal water mass movements could vary regionally and even locally.&#160; As a consequence, the tidal parameter controlled by the ocean loading effect could change over long-term observation periods and it should possibly be detectable as a trend or temporal variation of the tidal gravity parameters locally. Actually, a long-term change of the tidal parameters is observed for the main tidal waves like K1 and O1 in the diurnal and for M2 and K2 in the semi-diurnal frequency band. However, it is not clear if these changes can be correlated with sea level changes as observed from satellite data. On the other hand, surface and subsurface temperature fluctuations directly reveal the size of the thermal signal inherent to climate change.

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Climate change in the recent geological past and the near future. Predicting its impacts: a Review

Bulletin of the Geological Society of Greece ◽

10.12681/bgsg.20684 ◽

2019 ◽

Vol 55 (1) ◽

pp. 260

Author(s):

Constantinos Perisoratis

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Climatic Change ◽

Sea Level ◽

Scientific Community ◽

Climate Changes ◽

Late Quaternary ◽

The Earth ◽

Geological Past ◽

Near Future

The climate changes are necessarily related to the increase of the Earth’s temperature, resulting in a sea level rise. Such continuous events, were taking place with minor and greater intensity, during the alternation of warm and cool periods in the Earth during the Late Quaternary and the Holocene periods. However, a particularly significant awareness has taken place in the scientific community, and consequently in the greater public, in the last decades: that a climatic change will take place soon, or it is on-going, and that therefore it is important to undertake drastic actions. However, such a climatic change has not been recorded yet, and hence the necessary actions are not required, for the time being.

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Climate Change Impacts on a Mediterranean Coastal Wetland due to Sea Level Rise (L’Albufera de Valencia, Spain)

10.5194/egusphere-egu21-1599 ◽

2021 ◽

Author(s):

Clara E Estrela Segrelles ◽

Miguel Ángel Pérez Martín ◽

Gabriel Gómez Martínez

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Coastal Wetlands ◽

Coastal Wetland ◽

Water Volume ◽

Lake Ecosystem ◽

Lake Levels ◽

Short Term

Sea level rise produced by climate change severely affects coastal ecosystems. The increase in the area below sea level facilitates the penetration of the marine wedge and causes an increase in soil salinity. Coastal wetlands are areas of great ecological importance due to the richness of flora and fauna that inhabit them. A change in salinity conditions could lead to a reduction or loss of habitat for the wetland biota. Based on RCP4.5 and RCP8.5 CMIP5 multimodel scenarios, in the Western Mediterranean coast, the sea level will rise 0.16 m in the short term (2026 - 2045) and 0.79 m in 2100. Also, high-end scenarios indicate that sea level will rise between 1.35 m and 1.92 m in the long term.A sea level rise analysis has been developed in the coastal wetlands of J&#250;car River Basin District (JRBD). The results show that coastal wetlands are the mainly area affected in the JRBD, so the 90% of the area under the sea level are wetlands. L&#8217;Albufera de Valencia is the main wetland in this basin and, also the main wetland affected. It is an anthropized humid zone, regulated by users through gates to preserve the adequate water level for agricultural and environmental purposes such as rice cultivation around the lake and bird habitats conservation, especially in winter. The outcome of the study shows a significative increase in the area below the sea from 507 ha and 4.2 hm3 of water volume at present to 3,244 ha that represents 42.6 hm3 of water volume in the short term. In the long term, the area below the sea is 7,253 ha which means 118.4 hm3 of water volume in the percentile 50 scenario and, in the worst extreme scenario, it is 13,896 ha that represents 289.7 hm3 of water volume. This leads to a redefinition of the lake management levels as a climate change adaptation measure to prevent the lake salinization and severe impacts in the lake ecosystem. L&#8217;Albufera lake levels need to be increased in the next years to avoid the sea water penetration, related to the sea level rise. Thus, in the short term the lake levels must be increased around 0.16 m and, in the long term, L&#8217;Albufera levels must be increased around 0.8 m.

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Future sea level rise constrained by observations and long-term commitment

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1500515113 ◽

2016 ◽

Vol 113 (10) ◽

pp. 2597-2602 ◽

Cited By ~ 92

Author(s):

Matthias Mengel ◽

Anders Levermann ◽

Katja Frieler ◽

Alexander Robinson ◽

Ben Marzeion ◽

...

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Greenhouse Gas ◽

Sea Level ◽

Past Century ◽

Intergovernmental Panel ◽

Adaptation Measures ◽

Equilibrium Response ◽

Semiempirical Models

Sea level has been steadily rising over the past century, predominantly due to anthropogenic climate change. The rate of sea level rise will keep increasing with continued global warming, and, even if temperatures are stabilized through the phasing out of greenhouse gas emissions, sea level is still expected to rise for centuries. This will affect coastal areas worldwide, and robust projections are needed to assess mitigation options and guide adaptation measures. Here we combine the equilibrium response of the main sea level rise contributions with their last century's observed contribution to constrain projections of future sea level rise. Our model is calibrated to a set of observations for each contribution, and the observational and climate uncertainties are combined to produce uncertainty ranges for 21st century sea level rise. We project anthropogenic sea level rise of 28–56 cm, 37–77 cm, and 57–131 cm in 2100 for the greenhouse gas concentration scenarios RCP26, RCP45, and RCP85, respectively. Our uncertainty ranges for total sea level rise overlap with the process-based estimates of the Intergovernmental Panel on Climate Change. The “constrained extrapolation” approach generalizes earlier global semiempirical models and may therefore lead to a better understanding of the discrepancies with process-based projections.

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Long-Term Climate Change Commitment and Reversibility: An EMIC Intercomparison

Journal of Climate ◽

10.1175/jcli-d-12-00584.1 ◽

2013 ◽

Vol 26 (16) ◽

pp. 5782-5809 ◽

Cited By ~ 152

Author(s):

Kirsten Zickfeld ◽

Michael Eby ◽

Andrew J. Weaver ◽

Kaitlin Alexander ◽

Elisabeth Crespin ◽

...

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Co2 Emissions ◽

Air Temperature ◽

Surface Air Temperature ◽

Meridional Overturning Circulation ◽

Atmospheric Co2 ◽

Change Commitment

Abstract This paper summarizes the results of an intercomparison project with Earth System Models of Intermediate Complexity (EMICs) undertaken in support of the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5). The focus is on long-term climate projections designed to 1) quantify the climate change commitment of different radiative forcing trajectories and 2) explore the extent to which climate change is reversible on human time scales. All commitment simulations follow the four representative concentration pathways (RCPs) and their extensions to year 2300. Most EMICs simulate substantial surface air temperature and thermosteric sea level rise commitment following stabilization of the atmospheric composition at year-2300 levels. The meridional overturning circulation (MOC) is weakened temporarily and recovers to near-preindustrial values in most models for RCPs 2.6–6.0. The MOC weakening is more persistent for RCP8.5. Elimination of anthropogenic CO2 emissions after 2300 results in slowly decreasing atmospheric CO2 concentrations. At year 3000 atmospheric CO2 is still at more than half its year-2300 level in all EMICs for RCPs 4.5–8.5. Surface air temperature remains constant or decreases slightly and thermosteric sea level rise continues for centuries after elimination of CO2 emissions in all EMICs. Restoration of atmospheric CO2 from RCP to preindustrial levels over 100–1000 years requires large artificial removal of CO2 from the atmosphere and does not result in the simultaneous return to preindustrial climate conditions, as surface air temperature and sea level response exhibit a substantial time lag relative to atmospheric CO2.

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THE RELATIVE CONTRIBUTION OF SEA LEVEL RISE AND STORM EROSION TO LONG TERM NET COASTLINE RECESSION

Coastal Engineering Proceedings ◽

10.9753/icce.v36.sediment.3 ◽

2018 ◽

pp. 3

Author(s):

Roshanka L.-F. Ranasinghe ◽

David Wainwright ◽

Dave Callaghan ◽

Trang Duong

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Cumulative Effect ◽

Environmental Risks ◽

Recovery Cycle ◽

Mean Sea Level ◽

Relative Contribution ◽

Potential Climate Change

The potential Climate change (CC) impacts on coasts and associated socio-economic and environmental risks are widely recognised internationally. One of the most talked about CC impacts is coastline recession. Any increase in mean sea level is expected to result in an upward and landward shift of the entire active profile causing net coastline recession (Bruun, 1962). Another phenomenon that can result in net coastline recession is the cumulative effect of storm erosion. This is due to the hysteresis effect in the storm erosion/dune recovery cycle (Ranasinghe et al., 2012). But what causes more recession: storms or sea level rise? This is a commonly asked question, to which science-backed answers have not been presented to date. This paper addresses this question via the application of a physics based, probabilistic numerical model at a typical swell and storm beaches located in SE Australia and The Netherlands, respectively.

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Incremental improvements of 2030 targets insufficient to achieve the Paris Agreement goals

Earth System Dynamics ◽

10.5194/esd-11-697-2020 ◽

2020 ◽

Vol 11 (3) ◽

pp. 697-708

Author(s):

Andreas Geiges ◽

Alexander Nauels ◽

Paola Yanguas Parra ◽

Marina Andrijevic ◽

William Hare ◽

...

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Extreme Temperature ◽

Paris Agreement ◽

Climate Impacts ◽

Change Scenario ◽

Intergovernmental Panel ◽

Wide Range

Abstract. Current global mitigation ambition up to 2030 under the Paris Agreement, reflected in the National Determined Contributions (NDCs), is insufficient to achieve the agreement's 1.5 ∘C long-term temperature limit. As governments are preparing new and updated NDCs for 2020, the question as to how much collective improvement is achieved is a pivotal one for the credibility of the international climate regime. The recent Special Report on Global Warming of 1.5 ∘C by the Intergovernmental Panel on Climate Change has assessed a wide range of scenarios that achieve the 1.5 ∘C limit. Those pathways are characterised by a substantial increase in near-term action and total greenhouse gas (GHG) emission levels about 50 % lower than what is implied by current NDCs. Here we assess the outcomes of different scenarios of NDC updating that fall short of achieving this 1.5 ∘C benchmark. We find that incremental improvements in reduction targets, even if achieved globally, are insufficient to align collective ambition with the goals of the Paris Agreement. We provide estimates for global mean temperature increase by 2100 for different incremental NDC update scenarios and illustrate climate impacts under those median scenarios for extreme temperature, long-term sea-level rise and economic damages for the most vulnerable countries. Under the assumption of maintaining ambition as reflected in current NDCs up to 2100 and beyond, we project a reduction in the gross domestic product (GDP) in tropical countries of around 60 % compared to a no-climate-change scenario and median long-term sea-level rise of close to 2 m in 2300. About half of these impacts can be avoided by limiting warming to 1.5 ∘C or below. Scenarios of more incremental NDC improvements do not lead to comparable reductions in climate impacts. An increase in aggregated NDC ambition of big emitters by 33 % in 2030 does not reduce presented climate impacts by more than about half compared to limiting warming to 1.5 ∘C. Our results underscore that a transformational increase in 2030 ambition is required to achieve the goals of the Paris Agreement and avoid the worst impacts of climate change.

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Incremental improvements of 2030 targets insufficient to achieve the Paris Agreement goals

10.5194/esd-2019-54 ◽

2019 ◽

Author(s):

Andreas Geiges ◽

Paola Yanguas Parra ◽

Marina Andrijevic ◽

William Hare ◽

Alexander Nauels ◽

...

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Extreme Temperature ◽

Paris Agreement ◽

Climate Impacts ◽

Change Scenario ◽

Intergovernmental Panel ◽

Wide Range

Abstract. Current global mitigation ambition as under the Paris Agreement as reflected in the National Determined Contributions (NDCs) up to 2030 is insufficient to achieve the Agreement's 1.5 °C long term temperature limit. As governments are preparing new and updated NDCs for 2020, the question as to how much collective improvement is achieved is a pivotal one for the credibility of the international climate regime. The recent Special Report of the Intergovernmental Panel of Climate Change on Global Warming of 1.5 °C has assessed a wide range of scenarios that achieve the 1.5 °C limit. Those pathways are characterized by a substantial increase in near-term action and total greenhouse gas (GHG) emission levels about 50 % lower than what is implied by current NDCs. Here we assess the outcomes of different scenarios of NDC updating that fall short of achieving this 1.5 °C benchmark. We find that incremental improvements in reduction targets even if achieved globally, are insufficient to align collective ambition with the goals of the Paris Agreement. We provide estimates for global mean temperature increase by 2100 for different incremental NDC update scenarios and illustrate climate impacts under those scenarios including for extreme temperature, long-term sea level rise and economic damages for the most vulnerable countries. Under the assumption of maintaining ambition as reflected in current NDCs up to 2100 and beyond, we project a reduction in the Gross Domestic Product (GDP) in tropical countries of about 50–60 % compared to a no-climate change scenario and long-term sea-level rise of close to 2 m in 2300. About half of these impacts can be avoided by limiting warming to 1.5 °C, or below. Scenarios of more incremental NDC improvements do not lead to comparable reductions in climate impacts. An increase in 2030 of the aggregated NDC ambition of big emitters by 33 % does not deliver more than about half the potential reduction in climate impacts compared to limiting warming to 1.5 °C. Our results underscore that a transformational increase in 2030 ambition is required to achieve the goals of the Paris Agreement and avoid the worst impacts of climate change.

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IBSE approach to study climate change from 90 degrees

10.5194/egusphere-egu2020-8453 ◽

2020 ◽

Author(s):

Elena Lugaro

Keyword(s):

Climate Change ◽

Global Warming ◽

Sea Level Rise ◽

Sea Level ◽

Learning Experience ◽

Scientific Evidence ◽

Climate System ◽

Polar Regions ◽

Major Advance ◽

The Earth

&#160;Scientific evidence of climate warming is today clear and well admitted within the scientific community. It is crucial to educate students about the climate crisis we are facing and the consequences that will occur at global level.&#160;Climate science is a complex topic, involving a cross-curricular learning experience linking biology, geology, physics and chemistry.&#160; Within such a complex theme, Polar Science plays a crucial role to understand how global warming and climate change are affecting and will affect our planet. Polar Regions are indeed among the most fragile and vulnerable areas, regulating the equilibrium of the whole planet, and the effects of global warming are already showing great changes in these regions.In this work, the IBSE (Inquiry Based Science Education) approach has been proposed to 14-16 years old students, to analyse how climate change is affecting the North Pole and South Pole, and which are the effects on the planet. Within this approach, students work independently, learning through experiments planned by themselves about the key role the Polar Regions play in the Earth&#8217;s climate system. They conducted some experiments regarding two major processes that contribute to sea level rise, by establishing whether land ice, sea ice or both contributes to sea level rise, and by determining whether the warming of the oceans contributes to sea level rise.This test has shown valuable results about the involvement of the students and their understanding of the processes occurring at the Polar Regions and their links with the whole Earth&#8217;s climate system. With the IBSE approach, students practice and experiment several&#160;&#160; skills they do not usually use such as working in a team, communicate and interact with other students to answer question, formulate hypothesis, share their ideas and collaborate in a group to find methodologies and possible solutions. Moreover, the design of the experiments made up by themselves has revealed to be a major advance to make the students more aware of the key role the Polar Regions play in the Earth&#8217;s climate system.&#160;IBSE approach, student-centered and problem-centered, has confirmed to be a valuable tool to encourage creativity, innovation and collaboration in the classroom, engaging and motivating pupils.&#160;

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