Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Global Climate Change01:50

Global Climate Change

Throughout its ~4.5 billion year history, the Earth has experienced periods of warming and cooling. However, the current drastic increase in global temperatures is well outside of the Earth’s cyclic norms, and evidence for human-caused global climate change is compelling. Paleoclimatology, the study of ancient climate conditions, provides ample evidence for human-caused global climate change by comparing recent conditions with those in the past.
Magnetic Fields01:28

Magnetic Fields

A moving charge or a current creates a magnetic field in the surrounding space, in addition to its electric field. The magnetic field exerts a force on any other moving charge or current that is present in the field. Like an electric field, the magnetic field is also a vector field. At any position, the direction of the magnetic field is defined as the direction in which the north pole of a compass needle points.
A magnetic field is defined by the force that a charged particle experiences...
Magnetic Susceptibility and Permeability01:31

Magnetic Susceptibility and Permeability

In linear magnetic materials, like paramagnets and diamagnets, magnetization is proportional to the magnetic field intensity. The constant of proportionality, a dimensionless number, is called magnetic susceptibility. The value of the susceptibility depends on the type of material.
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
Magnetic Field Lines01:19

Magnetic Field Lines

The representation of magnetic fields by magnetic field lines is very useful in visualizing the strength and direction of the magnetic field. Each of the magnetic field lines forms a closed loop. The field lines emerge from the north pole (N), loop around to the south pole (S), and continue through the bar magnet back to the north pole.
Magnetic field lines follow several hard-and-fast rules:
Magnetic Declination01:19

Magnetic Declination

Magnetic declination is the angle between true north, which aligns with the Earth's rotational axis, and magnetic north, which follows the direction of the Earth's magnetic field. This discrepancy exists because the magnetic poles do not coincide with the geographic poles. The value of magnetic declination depends on the observer's location on Earth and is subject to changes over time due to the dynamic nature of the Earth's magnetic field.The declination is called eastern when magnetic north...
Magnetic Flux01:19

Magnetic Flux

The magnetic flux measures the number of magnetic field lines passing through a given surface area. The SI unit for magnetic flux is the weber (Wb). Magnetic flux is a scalar quantity. It depends on three factors: the strength of the magnetic field B, the area through which the field lines pass, and the relative orientation of the field with the surface area.
Suppose a surface is divided into elements of area dA. For each element, the component of the magnetic field that is normal to the...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Correction: Evidence of Cosmic Impact at Abu Hureyra, Syria at the Younger Dryas Onset (~ 12.8 ka): High-temperature melting at > 2200 °C.

Scientific reports·2025
Same author

RETRACTED: Shocked quartz at the Younger Dryas onset (12.8 ka) supports cosmic airbursts/impacts contributing to North American megafaunal extinctions and collapse of the Clovis technocomplex.

PloS one·2025
Same author

Submarine ash megabed fed by far-traveled, shoreline-crossing pyroclastic currents from a large explosive volcanic eruption.

Science advances·2025
Same author

RETRACTED: A 12,800-year-old layer with cometary dust, microspherules, and platinum anomaly recorded in multiple cores from Baffin Bay.

PloS one·2025
Same author

Magnetite particle size and spatial distribution may modulate neural oscillation in the human brain.

Scientific reports·2025
Same author

Retraction Note: A Tunguska sized airburst destroyed Tall el-Hammam a Middle Bronze Age city in the Jordan Valley near the Dead Sea.

Scientific reports·2025

Related Experiment Video

Updated: Jul 16, 2026

Tree Core Analysis with X-ray Computed Tomography
06:56

Tree Core Analysis with X-ray Computed Tomography

Published on: September 22, 2023

Magnetic record associated with tree ring density: possible climate proxy.

Gunther Kletetschka1, Petr Pruner, Daniela Venhodova

  • 1Institute of Geology, AS CR, Prague, 16502, Czech Republic. kletetschka@nasa.gov

Geochemical Transactions
|March 27, 2007
PubMed
Summary

Tree ring magnetic properties reveal past climate changes. Sequoia wood shows higher magnetic efficiency during warm periods and lower during the Little Ice Age, suggesting global climate patterns.

Related Experiment Videos

Last Updated: Jul 16, 2026

Tree Core Analysis with X-ray Computed Tomography
06:56

Tree Core Analysis with X-ray Computed Tomography

Published on: September 22, 2023

Area of Science:

  • Paleoclimatology
  • Geophysics
  • Environmental Science

Background:

  • Tree rings offer valuable archives for reconstructing past environmental conditions.
  • Magnetic properties of geological materials can serve as proxies for climate reconstruction.

Purpose of the Study:

  • To investigate the potential of magnetic signatures in sequoia tree rings as a paleo-climatic indicator.
  • To analyze magnetic properties of tree rings spanning 600-1700 A.D. to identify climate trends.

Main Methods:

  • Measurement of magnetic susceptibility (low and high-field), natural remanent magnetization (NRM), and saturation isothermal remanent magnetization (SIRM).
  • Assessment of magnetic stability using thermal and alternating field (AF) demagnetization techniques.
  • Analysis of magnetic data in relation to known climate periods like the Medieval Warm Epoch and the Little Ice Age.

Main Results:

  • Magnetic efficiency of sequoia tree rings was significantly higher (>1%) during the Medieval Warm Epoch (700-1300 A.D.) compared to the Little Ice Age (<1%).
  • Diamagnetic behavior correlated with higher tree ring density.
  • Blocking temperatures near 200°C suggest a thermal origin for the remanent magnetic component, influenced by local thermal conditions.

Conclusions:

  • The magnetic signature of tree rings is a sensitive indicator of past climate variations.
  • The recorded climate variations in sequoia tree rings suggest the Little Ice Age may have been a global phenomenon.
  • Maghemite is proposed as the likely magnetic carrier due to observed magnetic properties.