Kajian: Matahari dijangka akan 'tidur' dlm tempoh yang tertentu

Fenomena 'Mini ICE AGE' bakal berulang?
10 July 2015

A new study claims that between 2020 and 2030 solar cycles will cancel each other out.

This, will lead to a phenomenon known as the 'Maunder minimum' - which has previously been known as a mini ice age when it hit between 1646 and 1715, even causing London's River Thames to freeze over.


The Frozen Thames, 1677 - an oil painting by Abraham Hondius shows the old London Bridge during the Maunder Minimum. It caused London's River Thames to freeze over, and 'frost fairs' became popular.


Matahari yg dirakam pd tahun 2011, kelihatan tenang dan jelas. Tiada aktiviti. Saintis jangka kejadian seperti ini akan berlaku berterusan dalam tempoh 10 tahun, iaitu mulai dr tahun 2030 hingga 2040


Conventional wisdom holds that solar activity swings back and forth like a simple pendulum.

At one end of the cycle, there is a quiet time with few sunspots and flares.

At the other end, solar max brings high sunspot numbers and frequent solar storms. It's a regular rhythm that repeats every 11 years.

Reality is more complicated. Astronomers have been counting sunspots for centuries, and they have seen that the solar cycle is not perfectly regular.

Predictions from the model suggest that solar activity will fall by 60 per cent during the 2030s to conditions last seen during the 'mini ice age' that began in 1645, according to the results presented by Prof Valentina Zharkova at the National Astronomy Meeting in Llandudno.

The model predicts that the pair of waves become increasingly offset during Cycle 25, which peaks in 2022.

During Cycle 26, which covers the decade from 2030-2040, the two waves will become exactly out of synch and this will cause a significant reduction in solar activity.

'In cycle 26, the two waves exactly mirror each other � peaking at the same time but in opposite hemispheres of the Sun,' said Zharkova.


Apa itu THE MAUNDER MINIMUM?
Kewujudan tompokan [warna gelap] pada matahari menjadi minimum untuk tempoh yang panjang.


1645 to about 1715, when sunspots became exceedingly rare, as noted by solar observers of the time.

There is evidence that the Sun has had similar periods of inactivity in the more distant past, Nasa says.

'Over the cycle, the waves fluctuate between the northern and southern hemispheres of the Sun. Combining both waves together and comparing to real data for the current solar cycle, we found that our predictions showed an accuracy of 97%,' said Zharkova.


Montage of images of solar activity between August 1991 and September 2001 taken by the Yohkoh Soft X-ray Telecope, showing variation in solar activity during a sunspot cycle.

Zharkova and her colleagues derived their model using a technique called 'principal component analysis' of the magnetic field observations from the Wilcox Solar Observatory in California.

They examined three solar cycles-worth of magnetic field activity, covering the period from 1976-2008.

In addition, they compared their predictions to average sunspot numbers, another strong marker of solar activity.

All the predictions and observations were closely matched.

Iklan Atas Artikel

Iklan Tengah Artikel 1

Iklan Tengah Artikel 2

Iklan Bawah Artikel