Aus für den Golfstrom? Droht Europa die nächste Eiszeit? | Terra X plus

Summary

The video script discusses the Atlantic Ocean's Gulf Stream System, which transports warmth from the south to Europe. It explains the system's role in Europe's mild climate and the potential consequences of its weakening due to climate change. The script debunks the likelihood of an immediate ice age but highlights increased risks of extreme weather events like storms and heatwaves. It emphasizes the importance of climate protection to stabilize the Gulf Stream and mitigate the impacts of climate change.

Takeaways

• 🌊 The Gulf Stream System is a massive water current in the Atlantic, responsible for bringing heat from the south to Europe.
• 🔥 Despite its importance, the Gulf Stream is weakening, raising concerns about potential climatic changes.
• 🌍 The system is part of a global network of interconnected ocean currents, crucial for climate regulation.
• 🌡️ The Gulf Stream's warm surface water, up to 30 degrees Celsius, plays a significant role in Europe's mild climate.
• 🌀 The 'Atlantic Meridional Overturning Circulation' (AMOC), which includes the Gulf Stream, involves the overturning of massive water masses, with cold water sinking and warm water taking its place.
• 🌾 Europe's agriculture and climate are heavily dependent on the warmth provided by the Gulf Stream.
• ❄️ A collapse of the Gulf Stream System, as depicted in 'The Day after Tomorrow', could lead to a significant drop in temperature, though such a scenario is considered unlikely.
• 🌐 The melting of the Greenland Ice Sheet due to global warming is a serious threat to the Gulf Stream, as fresh water from melting ice is less dense and disrupts the circulation.
• 📉 Since 1950, the Gulf Stream has already lost 15% of its strength, and if climate change continues unchecked, it could become half as strong by the end of the century.
• 🌡️ While a weaker Gulf Stream could lead to cooler temperatures, the overall effect of climate change is likely to make Europe warmer, not colder.
• 🌪️ Changes in the Gulf Stream could also affect weather patterns, potentially leading to more frequent and severe storms and heatwaves.

Q & A

What is the Gulf Stream System and how does it affect Europe's climate?

The Gulf Stream System is a massive water current in the Atlantic Ocean that brings heat from the south to Europe. It is part of a larger circulation system known as the 'Atlantic Meridional Overturning Circulation' (AMOC). The Gulf Stream's warm surface water, up to 30 degrees Celsius, is transported northward where it transitions into the North Atlantic Current, which carries warmth to Europe, resulting in a mild climate.

Why is the Gulf Stream System weakening?

The Gulf Stream System is weakening due to global warming, which causes the melting of the Greenland Ice Sheet. The influx of large amounts of fresh water from the melting ice makes the surface water less dense, preventing it from sinking as effectively, which slows down the overall circulation and reduces the amount of heat transported to Europe.

What is the potential impact of a complete shutdown of the Gulf Stream System?

While a complete shutdown of the Gulf Stream System is not considered realistic in the near future, it could lead to a significant cooling of Europe by 5 to 10 degrees Celsius, similar to the conditions during the peak of the last ice age. However, climate protection measures could prevent such a drastic weakening of the Gulf Stream.

How does the melting of the polar ice caps in Antarctica relate to the Gulf Stream System?

The script does not directly link the melting of the Antarctic ice caps to the Gulf Stream System. Instead, it focuses on the impact of Greenland's melting ice sheet, which is closer and more directly influences the North Atlantic Current and the Gulf Stream System due to its proximity and the freshwater input into the North Atlantic.

What role does the freshwater from the melting ice sheets play in the Gulf Stream System?

Freshwater from melting ice sheets, particularly Greenland's, is a significant problem for the Gulf Stream System because it is lighter than saltwater. When the Gulf Stream incorporates this freshwater, it becomes less dense and cannot sink as effectively, which slows down the deep-water return flow and, consequently, the heat transport from the Gulf Stream.

What has been the observed decline in the strength of the Gulf Stream since 1950?

According to the script, the Gulf Stream has already lost 15 percent of its strength since 1950. If no action is taken against climate change, it could become even weaker and potentially unstable by the end of the century.

What are the current observable effects of the weakening Gulf Stream System?

The weakening of the Gulf Stream System is already observable in the form of warmer waters along the U.S. coast, leading to rising sea levels, and potentially more severe hurricanes and flooding. In Europe, it could lead to more frequent cold winter storms and heatwaves, as well as a potential decrease in summer rainfall.

How does the weakening of the Gulf Stream System affect the Jetstream?

The weakening of the Gulf Stream System could affect the Jetstream, a strong wind current high in the atmosphere, by causing it to waver. This could lead to the formation of a 'cold dome' in the North Atlantic, which might cause the Jetstream to meander, allowing hot air from the Sahara to reach Europe and contributing to heatwaves.

What are the potential agricultural impacts of the Gulf Stream System's weakening?

The weakening of the Gulf Stream System could lead to a combination of drier summers and hotter temperatures, which might harm agriculture by reducing rainfall and increasing the risk of wildfires, if no countermeasures are taken.

How does the script suggest we should prepare for the future in relation to the Gulf Stream System?

Instead of fearing an ice age, the script suggests that we should prepare for more frequent heatwaves and winter storms. It emphasizes the importance of climate protection to stabilize the Gulf Stream System and the Jetstream, mitigating the impacts of a weaker Gulf Stream on weather patterns and agriculture.

Outlines

00:00

🌊 The Gulf Stream System and Its Impact on Europe's Climate

The Gulf Stream System, a massive water current in the Atlantic Ocean, plays a crucial role in bringing warmth from the south to Europe. Named after the Gulf Stream, which flows from the U.S. coast towards the North Atlantic, this system is responsible for Europe's mild climate. The surface water of the Gulf Stream can reach up to 30 degrees Celsius, significantly warmer than the North Sea's maximum of 16 degrees. This warmth is transported northward, where it transitions into the North Atlantic Current, which carries the heat to Europe. The return journey involves colder, denser water that sinks to depths of up to 4,000 meters near Greenland, contributing to the 'Atlantic Overturning Circulation.' The system is vital for agriculture in Northern Europe, as many crops would not grow without the mild climate it provides. The script also addresses the hypothetical scenario of the Gulf Stream System failing, which could lead to a hostile ice age, as depicted in the 2004 film 'The Day after Tomorrow.' However, the real threat to the Gulf Stream is not a rapid melting of the Antarctic ice sheet, but rather the melting of the Greenland Ice Sheet due to global warming. This influx of fresh water, which is lighter than saltwater, disrupts the sinking process necessary for the return flow of the Gulf Stream, potentially slowing down the circulation and reducing the heat it brings to Europe. Research by Stefan Rahmstorf at the Potsdam Institute for Climate Impact Research has shown that the Gulf Stream has already lost 15% of its strength since 1950, and without action against climate change, it could become half as strong and unstable by the end of the century.

05:07

🌪️ Effects of a Weakening Gulf Stream on Weather Patterns

A weakening Gulf Stream System has observable effects on weather patterns, particularly along the U.S. coast and in Europe. In the U.S., the Gulf Stream's heat accumulates, leading to rising sea levels and an increased risk of severe flooding and hurricanes, although the depiction in films like 'The Day after Tomorrow' is exaggerated. In Europe, the effects are more complex, with the potential for more frequent cold winter storms and heatwaves, contrary to the expectation of cooling from a weaker Gulf Stream. The script explains that while the Gulf Stream's weakening might cool Europe over the year, it could also disrupt the Jet Stream, a high-altitude wind current that protects Europe from Saharan heat. This disruption could lead to the formation of a 'cold dome' in the North Atlantic, causing the Jet Stream to meander and allow hot Saharan air to reach Europe, contributing to heatwaves. Additionally, the weakening Gulf Stream could lead to reduced rainfall during European summers, potentially harming agriculture and increasing the risk of wildfires. The script concludes by emphasizing the need for climate protection to stabilize the Gulf Stream and Jet Stream, rather than preparing for an ice age.

Keywords

💡Gulf Stream System

The Gulf Stream System is a massive ocean current in the Atlantic Ocean that transports warm water from the southern regions to Europe. It plays a crucial role in regulating the climate of Europe by providing a mild climate. In the video, the weakening of this system is discussed as a potential environmental concern, with implications for climate patterns and agriculture.

💡Thermohaline Circulation

Also known as the Atlantic Meridional Overturning Circulation (AMOC), thermohaline circulation refers to the large-scale movement of ocean waters driven by differences in temperature and salinity. The video explains how warm water from the Gulf Stream cools and sinks in the North Atlantic, returning southward in a deep, cold current, which is a critical component of the Earth's climate system.

💡Climate Change

Climate change is a significant theme in the video, as it is linked to the melting of the Greenland Ice Sheet and the subsequent freshening of the North Atlantic, which can slow down the Gulf Stream. The video suggests that human-induced climate change could have profound effects on the Gulf Stream System, potentially leading to more extreme weather events and temperature fluctuations in Europe.

💡Greenland Ice Sheet

The Greenland Ice Sheet is a massive body of ice covering the majority of Greenland. In the context of the video, the melting of this ice sheet due to global warming contributes to the influx of fresh water into the North Atlantic, which can disrupt the Gulf Stream by making the surface waters less dense and less likely to sink, thus affecting the thermohaline circulation.

💡Freshwater Forcing

Freshwater forcing is the process by which an influx of fresh water, such as from melting ice sheets or increased precipitation, reduces the salinity of the ocean surface. The video explains that this can weaken the Gulf Stream by making the surface waters less dense, thus inhibiting the sinking of cold water necessary for the thermohaline circulation.

💡Jet Stream

The Jet Stream is a high-altitude, fast-flowing air current that influences weather patterns. The video suggests that a weakened Gulf Stream could affect the Jet Stream's stability, potentially leading to more extreme weather events such as heatwaves and winter storms in Europe.

💡Heatwaves

Heatwaves are prolonged periods of excessively hot weather. The video discusses how a weakened Gulf Stream could paradoxically lead to more frequent heatwaves in Europe, as the Jet Stream's altered path might allow for the penetration of hot air from the Sahara.

💡Winter Storms

Winter storms are severe weather events characterized by strong winds, heavy snowfall, or freezing rain. The video suggests that a weakened Gulf Stream could lead to more frequent winter storms in Europe, as the altered Jet Stream might allow for the mixing of cold and warm air masses.

💡Agricultural Impact

The video highlights the potential impact of a weakened Gulf Stream on European agriculture, suggesting that changes in temperature and precipitation patterns could affect crop growth and increase the risk of wildfires, which could have significant economic and environmental consequences.

💡Climate Protection

Climate protection refers to the various measures taken to mitigate the effects of climate change. The video concludes by emphasizing the importance of climate protection to stabilize the Gulf Stream System and prevent further disruptions to the climate and ecosystems.

Highlights

The Gulf Stream System is a massive water current in the Atlantic Ocean that brings heat from the south to Europe.

The ocean currents are constantly in motion, forming a global interconnected system.

The Gulf Stream, named after the stream flowing from the U.S. coast towards the North Atlantic, is part of the Gulf Stream System.

Surface water of the Gulf Stream can be up to 30 degrees warm, compared to the North Sea's maximum of 16 degrees.

The Gulf Stream's warmth is transported northward, where it transitions into the North Atlantic Current, bringing warmth to Europe and creating a mild climate.

After reaching Europe, the cooled and denser water masses of the Gulf Stream sink to depths of up to 4,000 meters near Greenland.

The deep flow then moves southward under other water masses, starting the cycle anew.

The Atlantic Meridional Overturning Circulation (AMOC), also known as the Gulf Stream System, is responsible for the exchange of warm and cold water masses.

Europe's agriculture and mild climate are significantly influenced by the warm water circulation of the Gulf Stream.

A collapse of the Gulf Stream System could potentially lead to a hostile ice age as depicted in the 2004 film 'The Day after Tomorrow'.

The melting of the Greenland Ice Sheet due to global warming could disrupt the Gulf Stream System more than the Antarctic Ice Sheet.

Freshwater from melting ice sheets is lighter than salty water, which can hinder the Gulf Stream's deep sinking and return flow.

Research at the Institute for Climate Impact Research in Potsdam indicates the Gulf Stream has already lost 15% of its strength since 1950.

Without action against climate change, the Gulf Stream could be half as strong and unstable by the end of the century.

Contrary to a sudden total collapse, a weakening of the Gulf Stream is more likely, leading to colder European winters but warmer summers due to global warming.

The Gulf Stream's weakening could also affect the Jet Stream, potentially causing more frequent heatwaves and winter storms in Europe.

Climate protection efforts are crucial to stabilize the Gulf Stream and Jet Stream, preventing extreme weather events and their impacts on agriculture and wildfires.

Transcripts

Das Golfstrom-System ist ein gewaltiger Wasserstrom im Atlantik, der Wärme vom Süden nach Europa bringt.

Doch der Strom, der schwächelt. Droht uns jetzt eine neue Eiszeit? Ich bin Carla und ich erklär euch heute mal das Golfstrom-System!

Erstmal auf Anfang: Unsere Ozeane sind ständig in Bewegung.

Auf der ganzen Welt zirkulieren gewaltige Meeresströmungen, alle miteinander verbunden.

Im Atlantik bilden sie ein gemeinsames System: das “Golfstrom-System”!

Es ist nach dem Golfstrom benannt, der von der Küste der USA Richtung Nordatlantik strömt.

Sein Oberflächenwasser ist bis zu 30 Grad warm! Zum Vergleich: Unser Nordsee-Wasser wird höchstens 16 Grad warm!

Seine Wärme transportiert der Golfstrom gen Norden, wo er in den Nordatlantikstrom übergeht.

Der bringt die Wärme dann nach Europa. Das sorgt bei uns für ein mildes Klima.

Danach machen sich die Wassermassen auf den Rückweg. Sie sind jetzt viel kälter, also auch dichter und schwerer.

Bei Grönland sinkt der Strom deshalb bis zu 4.000 Meter in die Tiefe.

In dieser Tiefe fließt er dann unter anderen Wassermassen hinweg gen Süden, wo wieder alles von vorn beginnt!

Weil im Golfstrom-System riesige Wassermassen „umgewälzt“ werden, also kaltes Wasser absinkt und warmes nachkommt, wird es auch „Atlantische Umwälzzirkulation“ genannt.

Europa hat der Zirkulation des warmen Wassers viel zu verdanken.

Große Teile unserer Landwirtschaft hängen von der Wärme und dem milden Klima ab, die sie uns beschafft.

Viele Kulturpflanzen ließen sich in Nordeuropa sonst wahrscheinlich gar nicht anbauen.

Okay, wir machen jetzt mal so ein kleines Gedankenexperiment: Was wäre denn, wenn das Golfstrom-System irgendwann mal komplett ausfallen würde?

Würde Europa dann ohne seine Wärme in einer lebensfeindlichen Eiszeit versinken?

Ein ähnliches Horror-Szenario gab es 2004 auch schonmal in dem Film „The Day after Tomorrow“.

Die USA und Europa wurden nach dem Ausfall des Golfstrom-Systems von Überschwemmungen und Hurrikans heimgesucht und das Ganze endete in einer Eiszeit!

Auslöser der Katastrophe im Film ist ein schnelles Abschmelzen der polaren Eiskappe in der Antarktis.

Aber was hat die Antarktis mit dem weit entfernten Golfstrom-System zu tun?

Und ist es reine Science-Fiction, dass das Abschmelzen von Eisschilden die Strömung stoppen könnte?

Die traurige Antwort ist: Nein, reine Science-Fiction ist das leider nicht!

Wobei es eher das Abschmelzen eines nördlichen Eisschildes ist, das dem Golfstrom-System zusetzen könnte: nämlich Grönlands Eisschild!

Grund für sein Schmelzen ist die Erderwärmung. So werden Unmengen bislang gefrorenes Süßwasser verflüssigt und in den Nordatlantik geleitet.

Noch mehr Süßwasser aber dringt vom Nordpolarmeer ein, das wegen vermehrter Niederschläge „versüßt“ – auch eine Folge des Klimawandels!

Dieses süße Oberflächenwasser ist für das Golfstrom-System ein großes Problem:

Denn Süßwasser ist leichter als salzhaltiges Wasser!

Wenn der Strom es aufnimmt, wird er also leichter und kann nicht mehr so gut in die Tiefe absinken, um zurückzufließen.

Dadurch wird die Strömung insgesamt abgebremst, denn so muss ja auch weniger Wasser nachströmen – und das heißt auch weniger Wärme vom Golfstrom!

Wie genau sich die Strömung verändert, das untersucht dieses Institut für Klimafolgenforschung in Potsdam.

Hier forscht der Ozean- und Klimaexperte Stefan Rahmstorf. Das Golfstrom-System beschäftigt ihn jetzt schon seit 30 Jahren.

Und das hat er herausgefunden: Seit 1950 hat die Strömung bereits 15 Prozent ihrer Kraft verloren.

Bis Ende des Jahrhunderts könnte sie nur noch halb so stark sein und sogar instabil werden, wenn wir nichts gegen die Klimaerwärmung unternehmen!

Aber was bedeutet das jetzt für Europa?

Droht uns ohne das Golfstrom-System eine neue Eiszeit, ähnlich wie im Hollywood-Szenario, wo ganze Städte vom Eis verschlungen werden?

Nein, das ist ganz klar übertrieben! Denn die Strömung wird ja erstmal nur schwächer.

Ein plötzlicher Totalausfall des Golfstrom-Systems wie im Film ist nicht realistisch.

Wir müssten laut einer Studie der Uni Oregon nochmal 300 Jahre den Klimawandel vorantreiben, damit die Gefahr eines Ausfalls bei knapp 50:50 läge.

Ein solcher Totalausfall könnte Europa zwar um 5 bis 10 Grad abkühlen – also etwa so kalt wie zum Höhepunkt der letzten Eiszeit.

ABER: mit Klimaschutz können wir eine so starke Abschwächung des Golfstrom-Systems wahrscheinlich verhindern.

Und gleichzeitig wird es in Europa wegen der Erderwärmung ja auch immer wärmer!

Klimaforscher Stefan Rahmstorf hält diese Entwicklung sogar für stärker, als die Abkühlung durch das schwache Golfstrom-System.

Letztendlich sollte es bei uns also erst einmal wärmer, als kälter werden!

Merken wir denn dann heute überhaupt schon etwas vom schwachen Golfstrom-System? Oh ja, das tun wir!

An der Küste der USA zum Beispiel staut sich die Wärme des Golfstroms an und der Meeresspiegel steigt.

Forscher rechnen dort mit heftigeren Überschwemmungen und Hurrikans.

Denn warmes Wasser ist für Hurrikans wie Treibstoff – auch wenn ihr Ausmaß in Hollywood-Filmen wie "The Day after Tomorrow" stark übertrieben wurde!

Und hier in Europa? Hier werden wahrscheinlich zwei Dinge häufiger: frostige Winterstürme und – aufgepasst! – auch Hitzewellen, wie dieses Jahr in Südeuropa!

Jetzt fragt ihr euch: Hitzewellen? Das ist doch total widersprüchlich!

Ein schwächeres Golfstrom-System sollte Europa doch eigentlich abkühlen. Ja, übers Jahr verteilt tut es das auch!

Aber dazu kommt noch ein zweiter Effekt, den die schwache Strömung laut einer Studie haben könnte, hoch oben in der Luft:

Sie könnte den Jetstream ins Wanken bringen!

Der Jetstream ist ein gewaltiger Windstrom in großer Höhe, der mit mehreren Hundert km/h von den USA Richtung Europa saust.

Flugzeuge nutzen ihn deshalb auch als Rückenwind, wenn sie über den Atlantik „jetten“.

Für uns hier aber viel wichtiger:

Der Jetstream weht so stark über Europa, dass er uns meistens vor dem Einfall anderer Luftströme beschützt: zum Beispiel heißer Luft aus der Sahara.

Die Abschwächung des Golfstrom-System könnte den Kurs des Jetstreams künftig aber zunehmend stören!

Sie führt nämlich im Nordatlantik zur Ausbildung einer gigantischen „Kälteblase“.

Der Jetstream neigt wahrscheinlich dazu solche Kältegefälle zu umkurven, wenn sie stark genug sind.

Er gerät dann ins Wanken, schlägt also Wellen, die über Europa teils wochenlang stehenbleiben und Platz machen für den Einfall heißer Sahara-Luft.

Das hat in Deutschland vermutlich zu den langen Hitzewellen der letzten zwei Jahrzehnte geführt.

Gleichzeitig könnte mit der Kraft des Golfstrom-Systems in Europas Sommer auch der Regen abnehmen.

Diese Kombination aus Trockenheit und Hitze könnte unserer Landwirtschaft schaden und zugleich Waldbrände verstärken – wenn wir jetzt nicht gegensteuern!

Anstatt auf eine Eiszeit sollten wir uns also eher auf weitere Hitzewellen und Winterstürme einstellen.

Ein Grund mehr, Golfstrom-System und Jetstream wieder durch Klimaschutz zu stabilisieren!

Wo ist der kälteste Ort an dem ihr schon wart? Schreibt es uns in die Kommentare und vergesst das Abo nicht, damit ihr kein Video mehr verpasst!