Doxa: Dramatic

A very dramatic view of how a glacier can melt:

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Meta:

What happens when there is a calving event from Greenland ie when a smallish glacier breaks off. Does it stay close, move away; how often does this happen?

When a glacier calves, it can send icebergs floating into the ocean. Here's what typically happens:

Initial Breakoff: A chunk of ice breaks off the glacier, often with a massive splash.

Iceberg Drift: The newly formed iceberg floats away, carried by ocean currents and winds.

Melting and Fragmentation: As it drifts, the iceberg melts and breaks into smaller pieces, eventually disappearing.

Calving events happen regularly, with some glaciers calving multiple times a day, while others may go years between events. Greenland's glaciers calve thousands of icebergs annually, contributing to sea level rise.

The frequency and size of calving events depend on factors like:

Glacier speed and thickness

Ocean temperatures and currents

Weather patterns

Some notable glaciers, like Jakobshavn Isbræ, calve massive icebergs relatively frequently, while others may be more stable.

Would you like to know more about specific glaciers or the impact of calving events on sea levels?

Surely it must take an awful lot of water to raise the planet's sea level. How long does it taker for melt ot be distributed over the whole planet?

The process of sea level rise is complex, but let's break it down. When ice melts, the water doesn't immediately distribute evenly across the globe. Instead, it takes time for the meltwater to mix with the oceans.

Key Factors Influencing Distribution:

Ocean Currents: Warm and cold currents help distribute heat and meltwater around the globe.

Gravity: Meltwater from Greenland, for example, initially raises sea levels more in the North Atlantic.

Earth's Rotation: The Coriolis effect influences ocean circulation patterns.

Distribution Timeframe:

Months to Years: Meltwater can circulate within ocean basins (e.g., North Atlantic) within months to a few years.

Decades to Centuries: Global ocean circulation patterns, like the thermohaline circulation, distribute heat and meltwater worldwide over decades or centuries.

The process is ongoing, and sea level rise is already affecting coastlines globally. Would you like to know more about the regional impacts of sea level rise or how it's affecting specific areas?

Do we get more melt from the Artic or the Antartic?

The Arctic is experiencing more melt than Antarctica. In fact, Arctic sea ice has been declining at a substantial rate, while Antarctic sea ice has been increasing, albeit at a slower rate. However, it's worth noting that Antarctica's ice sheet is much larger than the Arctic's, and its melt could have more significant implications for sea level rise.

The Arctic's accelerated warming is primarily driven by human activities, such as burning fossil fuels, which contribute to climate change. This warming is amplified by feedback loops, like the ice-albedo effect, where melting ice exposes darker ocean surfaces that absorb more solar radiation.

In contrast, Antarctica's ice sheet is influenced by different factors, including ocean currents and wind patterns. While some areas of Antarctica have experienced ice loss, others have seen ice gain, resulting in a net increase in sea ice extent.

Would you like to know more about the implications of Arctic ice melt or how climate change is affecting Antarctica's ice sheet?

So the sea level is currently higher in the Northern Hemisphere, and the water is warmer??

The Northern Hemisphere's sea level is indeed slightly higher, and the water is warmer compared to the Southern Hemisphere. This is mainly due to the uneven distribution of land and ocean water. The Northern Hemisphere has more land, which absorbs and retains heat, warming the surrounding oceans.

Key Factors Contributing to this Difference:

Land-Ocean Distribution: The Northern Hemisphere has more land, leading to increased heat absorption and warmer ocean temperatures.

Ocean Currents: Warm currents like the Gulf Stream transport heat from the equator to higher latitudes, warming the North Atlantic.

Solar Radiation: The Northern Hemisphere receives more solar radiation during its summer months, contributing to warmer ocean temperatures.

As a result, the average annual temperature of the Northern Hemisphere's oceans is around 19.4°C (67°F), while the Southern Hemisphere's oceans average around 16.1°C (61°F).

Would you like to know more about how ocean currents impact global climate patterns or the effects of warmer ocean temperatures on marine ecosystems?

Are the glaciers of the Northern hemisphere tracked. I am assuming no one wants to see another Titanic event!?

Glaciers in the Northern Hemisphere are indeed tracked to prevent maritime disasters like the Titanic. The Canadian Ice Service and the International Ice Patrol use a combination of satellite data, aerial reconnaissance, and ground-based tracking systems to monitor icebergs and sea ice.

Tracking Methods:

Satellite Imagery: Synthetic Aperture Radar (SAR) and optical satellites help identify and track icebergs.

Aerial Reconnaissance: Aircraft fly over ice-infested waters to gather data.

Ground-Based Tracking: Beacons and sensors deployed on icebergs provide real-time data.

The Global Land Ice Measurements from Space (GLIMS) initiative also provides comprehensive data on glaciers worldwide, including those in the Northern Hemisphere.

Would you like to know more about the technologies used for glacier tracking or how climate change is affecting glaciers?

How many glaciers might be tracked on a given day?

The Global Land Ice Measurements from Space (GLIMS) initiative tracks around 200,000 glaciers worldwide, with data from approximately 70% of them currently available. The GLIMS Glacier Database provides timely data on these glaciers, using satellite imagery from ASTER and Landsat, as well as historical observations.

Tracking Methods:

Satellite Imagery: ASTER and Landsat satellites capture images of glaciers, helping track changes in size, shape, and movement.

Ground-Based Observations: Regional Coordinators and glaciological institutions contribute data on glacier extent, snowlines, and other attributes.

Web-Based Tools: The GLIMS Glacier Viewer and Text Search Interface allow users to explore and download glacier data.

Would you like to know more about the specific data available for glaciers in the Northern Hemisphere or how climate change is affecting glaciers globally?

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Tell me about the Jakobshaven glacier. It is an 'outlet glacier'!?

The Jakobshavn Glacier, also known as Sermeq Kujalleq, is a massive outlet glacier in West Greenland. It's one of the fastest-moving glaciers in the world, draining about 6.5% of the Greenland ice sheet and producing around 10% of all Greenland icebergs. Every year, it calves off approximately 35 billion tonnes of icebergs, some of which can be as tall as 1 km.

This glacier has been extensively studied for over 250 years, providing valuable insights into climate change and icecap glaciology. Jakobshavn Glacier's ice flow velocity can reach up to 50 meters per day, making it a significant contributor to global sea level rise. In fact, it's responsible for about 4% of the increase in global sea level in the 20th century.

The glacier's rapid movement is attributed to factors like ocean warming, ice calving, and changes in ice sheet dynamics. Its terminus has retreated significantly, with a notable acceleration in ice loss since the 1990s.

Would you like to know more about the impact of climate change on Jakobshavn Glacier or its role in global sea level rise?

This glacier is moving relative to what?

The Jakobshavn Glacier is moving relative to its bedrock and the surrounding landscape. It's an outlet glacier, meaning it's a pathway for ice to flow from the Greenland ice sheet into the ocean.

Reference Points:

Bedrock: The glacier's ice flows over the underlying bedrock, which is relatively stationary.

Terminus: The glacier's terminus, or snout, is the point where it meets the ocean. This is often used as a reference point to measure the glacier's movement.

Fixed points on land: Scientists use fixed points on land, like rock outcrops or survey markers, to track the glacier's movement over time.

The glacier's movement is typically measured in terms of its flow velocity, which can be up to 50 meters per day. This movement is driven by gravity, ice pressure, and other factors like ocean warming and ice calving.

Would you like to know more about how scientists measure glacier movement or the implications of Jakobshavn Glacier's rapid flow?

Where is it on the map?

Jakobshavn Glacier, also known as Ilulissat Glacier or Sermeq Kujalleq, is located in West Greenland, near the town of Ilulissat. It's situated at latitude 69.1667° N and longitude -49.8333° W, ending at the sea in the Ilulissat Icefjord.

To give you a better idea, it's about 45 km east of the coast, with an elevation of around 283 meters. You can explore its location on OpenStreetMap or Google Maps for a more detailed view.

Would you like to know more about its movement or impact on global sea levels?