Category Earth Science

Here, cold winds blowing off the ocean cause thick fog to form and drift inland. Water droplets in the fog soon dry up under the hot Sun, rather than falling as rain, leaving the land below very dry.

The Atacama Desert is one of the driest places on Earth. The Atacama is in the country of Chile in South America. In an average year, much of this desert gets less than 1 millimeter (0.04 inch) of rain! That makes it 50 times drier than Death Valley in California.

It is hard to survive in the Atacama Desert. Few people, animals, plants, or even microbes live there. But the desert isn’t completely without life. Some people and other living creatures do get by in the Atacama.

The north end of the Atacama Desert is near the border of Chile and Peru. It runs about 1,000 km (600 miles) south from there. It has an area of 140,000 km (54,000 square miles). That is about the size of the state of New York in the U.S.A.

The Atacama is the driest hot desert in the world. There are some weather stations in the Atacama where there has never been any rain! Not all deserts are hot. The Dry Valleys in Antarctica are cold deserts. They are the driest deserts on Earth.

 

Picture Credit : Google

The largest cold deserts are in Central Asia, usually in high, flat areas. They are very dry, like all deserts, but are also very cold for most of the time. During the long winters, temperatures often drop as low as -40° C (-40° F).

Gobi, also called Gobi Desert, great desert and semidesert region of Central Asia. The Gobi (from Mongolian Gobi, meaning “waterless place”) stretches across huge portions of both Mongolia and China.The Gobi is overall a cold desert, with frost and occasionally snow occurring on its dunes. Besides being quite far north, it is also located on a plateau roughly 910–1,520 metres (2,990–4,990 ft) above sea level, which contributes to its low temperatures. An average of approximately 194 millimetres (7.6 in) of rain falls annually in the Gobi. Additional moisture reaches parts of the Gobi in winter as snow is blown by the wind from the Siberian Steppes. These winds may cause the Gobi to reach ?40° C (?40° F) in winter to 45° C (113° F) in summer.

However, the climate of the Gobi is one of great extremes, combined with rapid changes of temperature of as much as 35° C (63° F). These can occur not only seasonally but within 24 hours.

 

Picture Credit : Google

Temperatures often reach 50° C (122° F) or higher during the day in hot deserts. But at night, it can be very cold. Most hot deserts are near the equator, where there is strong sunlight all year round.

The Sahara is the largest hot desert in the world, and the third largest desert behind Antarctica and the Arctic, which are both cold deserts. The Sahara is one of the harshest environments on Earth, covering 3.6 million square miles (9.4 million square kilometers), nearly a third of the African continent, about the size of the United States (including Alaska and Hawaii).

The Sahara desert has a variety of land features, but is most famous for the sand dune fields that are often depicted in movies. The dunes can reach almost 600 feet (183 meters) high but they cover only about 15 percent of the entire desert. Other topographical features include mountains, plateaus, sand- and gravel-covered plains, salt flats, basins and depressions. Mount Koussi, an extinct volcano in Chad, is the highest point in the Sahara at 11,204 feet (3,415 m), and the Qattara Depression in Egypt is the Sahara’s deepest point, at 436 feet (133 m) below sea level.

 

Picture Credit : Google

About third of Earth’s surface is covered by deserts. They are areas that get little or no rain, so they are extremely dry. Only a few species of animals and plants can survive in them. We usually think of deserts as very hot places, but some are very cold.

Deserts are formed by weathering processes as large variations in temperature between day and night put strains on the rocks which consequently break in pieces. Although rain seldom occurs in deserts, there are occasional downpours that can result in flash floods. Rain falling on hot rocks can cause them to shatter and the resulting fragments and rubble strewn over the desert floor are further eroded by the wind. This picks up particles of sand and dust and wafts them aloft in sand or dust storms. Wind-blown sand grains striking any solid object in their path can abrade the surface. Rocks are smoothed down, and the wind sorts sand into uniform deposits. The grains end up as level sheets of sand or are piled high in billowing sand dunes. Other deserts are flat, stony plains where all the fine material has been blown away and the surface consists of a mosaic of smooth stones. These areas are known as desert pavements and little further erosion takes place. Other desert features include rock outcrops, exposed bedrock and clays once deposited by flowing water. Temporary lakes may form and salt pans may be left when waters evaporate. There may be underground sources of water in the form of springs and seepages from aquifers. Where these are found, oases can occur.

 

Picture Credit : Google

Southern Peru 2001

The 2001 southern Peru earthquake occurred at 20:33:15 UTC (15:33:15 local time) on June 23 with a moment magnitude of 8.4 and a maximum Mercalli intensity of VIII (Severe).

At least 74 people were killed, including 26 killed by a tsunami. At least 2,687 were injured, 17,510 homes were destroyed and 35,549 homes damaged in the Arequipa-Camana-Tacna area. An additional 64 people were missing due to the tsunami in the Camana-Chala area. Landslides blocked highways in the epicentral area. Many of the historic buildings in Arequipa were damaged or destroyed, including the left tower of the Basilica Cathedral of Arequipa.

Denali 2002

The 2002 Denali earthquake occurred at 22:12:41 UTC (1:12 PM Local Time) November 3 with an epicenter 66 km ESE of Denali National Park, Alaska, United States. This 7.9 Mw earthquake was the largest recorded in the United States in 37 years (after the 1965 Rat Islands earthquake). 

Minor damage was reported over a wide area but the only examples of severe damage were on highways that crossed the fault trace and areas that suffered liquefaction, e.g. Northway Airport. Several bridges were damaged but none so severely that they were closed to traffic.

Hokkaid? 2003

The 2003 Hokkaid? earthquake, scientifically named the 2003 Tokachi-Oki earthquake, occurred off the coast of Hokkaid?, Japan on 26 September at 04:50 local time.

 The tremor affected a total of 36 local rivers, including the major Abashiri and Ishikari Rivers. Many properties received considerable damage, and although there were no deaths, 849 people sustained injuries.

Sumatra 2004

Ans: This massive earthquake had a force of 9.3! It triggered a series of huge waves, called for thousands of kilometers across the Indian Ocean, killing 280,000 people. The resulting tsunami affected 12 nations around the Indian Ocean, with Indonesia suffering the greatest damage. In Aceh, the northern province of Sumatra, the United Nations (UN) Field Office reported approximately 131,000 people confirmed dead and 37,000 missing. With more than 80,000 houses sustaining major damage or collapse, the UN estimated that more than 500,000 people were displaced from their homes in Sumatra alone. In addition to the massive damage to housing, utilities, roads, and bridges, the disaster significantly disrupted the social fabric and government of the affected communities.

Nias–Simeulue 2005

The 2005 Nias–Simeulue earthquake occurred on 28 March off the west coast of northern Sumatra, Indonesia. At least 915 people were killed, mostly on the island of Nias. The event caused panic in the region, which had already been devastated by the massive tsunami triggered by the 2004 Indian Ocean earthquake, but this earthquake generated a relatively small tsunami that caused limited damage. It was the third most powerful earthquake since 1965 in Indonesia.

On the Indonesian island of Nias, off the coast of Sumatra, hundreds of buildings were destroyed. The death toll on Nias was at least one thousand, with 220 dying in Gunungsitoli, the island’s largest town. Nearly half of Gunungsitoli’s population (27,000) fled.

Kuril Islands 2006

The 2006 Kuril Islands earthquake occurred on November 15 at 8:14:16 pm JST with an Mw magnitude of 8.3 and a maximum Mercalli intensity of IV (Light). This megathrust earthquake was the largest event in the central Kuril Islands since 1915 and generated a small tsunami that affected the northern Japanese coast. This earthquake is considered a doublet of the 2007 Kuril Islands earthquake that hit the same area on January 13, 2007.

Sumatra 2007

The September 2007 Sumatra earthquakes were a series of megathrust earthquakes that struck the Sunda Trench off the coast of Sumatra, Indonesia, with three of magnitude 7 or greater. A series of tsunami bulletins was issued for the area. The most powerful of the series had a magnitude of 8.4, which makes it in the top 20 of the largest earthquakes ever recorded on a seismograph.

It caused buildings to sway in Jakarta, and some buildings were reported to have collapsed in the city of Bengkulu, Bengkulu Province, about 100 km from the epicenter. The earthquake also led to a power outage in Bengkulu, which crippled communications. The death toll of the earthquakes is 21 with 88 people injured.

China 2008

 A force-8 earthquake struck Sichuan Province, China, in 2008. Huge chunks, of rock fell down from the mountains, smashing towns and villages. Tremors were felt up to 1,700 km (1,060 miles) away.

Almost 90,000 people were counted as dead or missing and presumed dead in the final official Chinese government assessment; the officially reported total killed included more than 5,300 children, the bulk of them students attending classes. In addition, nearly 375,000 people were injured by falling debris and building collapses. Hundreds of dams, including two major ones, were found to have sustained damage.

Italy 2009

In 2009, an earthquake measuring 6.3 on a seismograph struck L’Aquila in central Italy. Many buildings collapsed and around 300 people died. Thousands of smaller earthquakes, called aftershocks, followed.

By September 2009 vigorous assistance efforts had succeeded in moving some of the dispossessed into new homes, though thousands remained housed in temporary facilities. The town’s historic centre remained off-limits more than a year after the quake as restoration efforts proceeded slowly, and officials involved in the reconstruction effort were later investigated for wrongdoing in the awarding of public contracts.

Chile 2010

The 2010 Chile earthquake occurred off the coast of central Chile on Saturday, 27 February at 03:34 local time (06:34 UTC), having a magnitude of 8.8 on the moment magnitude scale, with intense shaking lasting for about three minutes. 

 According to official sources, 525 people lost their lives, 25 people went missing and about 9% of the population in the affected regions lost their homes.

Pacific coast of T?hoku 2011

The 2011 earthquake off the Pacific coast of T?hoku  was a magnitude 9.0–9.1 (Mw) undersea megathrust earthquake off the coast of Japan that occurred at 14:46 JST (05:46 UTC) on Friday 11 March 2011, with the epicentre approximately 70 kilometres (43 mi) east of the Oshika Peninsula of T?hoku and the hypocenter at an underwater depth of approximately 29 km (18 mi). 

 It was the most powerful earthquake ever recorded in Japan, and the fourth most powerful earthquake in the world since modern record-keeping began in 1900.

Indian Ocean 2012

The 2012 Indian Ocean earthquakes were magnitude 8.6 and 8.2 Mw? undersea earthquakes that struck near the Indonesian province of Aceh on 11 April at 15:38 local time.

Four people in their 60s and 70s in Banda Aceh, and a 39-year-old man in Lhokseumawe died from heart attacks or shock. Injuries were reported in Aceh Singkil, including a child who was critically injured by a falling tree. The quake prompted people in Indonesia, Thailand and India to leave their homes and offices in fear of tsunamis. 

Okhotsk Sea 2013

The 2013 Okhotsk Sea earthquake occurred with a moment magnitude of 8.3 at 15:44:49 local time (05:44:49 UTC) on 24 May. It had an epicenter in the Sea of Okhotsk and affected primarily (but not only) Asian Russia, especially the Kamchatka Peninsula where the shaking lasted for five minutes.

Iquique 2014

The 2014 Iquique earthquake struck off the coast of Chile on 1 April, with a moment magnitude of 8.2, at 20:46 local time (23:46 UTC).

Four men died of heart attacks and one woman was reportedly crushed to death when a wall collapsed. A loader was crushed by a falling metal structure and died of the injuries afterwards. Around 80,000 were displaced by the event. Electricity and water services were interrupted in the regions of Arica y Parinacota and Tarapacá.

Illapel 2015

The 2015 Illapel earthquake occurred 46 km (29 mi) offshore from Illapel (Coquimbo region, Chile) on September 16 at 19:54:33 Chile Standard Time (22:54:33 UTC), with a moment magnitude of 8.3. 

 Illapel, an inland city of some 30,000 residents, was reported immediately to be without electricity or drinking water. Two days after the quake, about 90,000 people were still without electricity. On September 21, officials were reporting over 9,000 people had been left homeless by the quake.

Ecuador 2016

At 18:58 ECT on April 16, a 7.8 Mw earthquake struck the coast of Ecuador approximately 27 km (17 mi) south-southeast of Muisne, in the province of Esmeraldas, at a depth of 20.6 km (12.8 mi). At least 676 people were killed and more than 16,600 others were injured in the earthquake. It was the worst natural disaster to hit Ecuador since the 1949 Ambato earthquake.

Chiapas 2017

The 2017 Chiapas earthquake struck at 23:49 CDT on 7 September (local time; 04:49 on the 8th UTC) in the Gulf of Tehuantepec off the southern coast of Mexico, near state of Chiapas, approximately 87 kilometres (54 mi) southwest of Pijijiapan (alternately, 101 kilometres (63 mi) south-southwest of Tres Picos), with a Mercalli intensity of IX (Violent).

 Within Chiapas, an estimated 1.5 million people were affected by the earthquake, with 41,000 homes damaged. Jose Calzada, Minister of Agriculture, reported that at least 98 people had died in the earthquake, including 78 in Oaxaca, 16 in Chiapas and 4 in Tabasco.

Fiji 2018

A powerful 8.2 magnitude earthquake occurred in the Pacific Ocean near the islands of Fiji and Tonga on Sunday morning local time, according to the United States Geological Survey (USGS). 

The epicentre of the quake was located 281 km northeast of the Ndoi Island in Fiji at a depth of 560 kilometres. Fiji is located in the Ring of Fire, an area in the basin of the Pacific Ocean, which is vulnerable to frequent earthquakes and volcanic eruptions.

 

Picture Credit : Google

Earthquakes that a seismograph records as having a force of 2.5-4 are felt as mild tremors. They cause little or no damage, although trees may sway and windows rattle.

Earthquakes are the vibrations caused by rocks breaking under stress against an underground surface called a fault plane while a tremor is an involuntary movement of earth surface caused by stress in the underground rocks. They are both signs of seismic movement within the earth.

The rumblings being investigated belong to the tectonic tremor, a less hazardous form of seismic activity that occurs far deeper into the earth’s core than the devastating earthquakes that occur much closer to the earth’s surface.

One major difference between tectonic tremor and earthquakes is that tectonic tremor causes relatively weak ground shaking and is not cause for immediate concern.

 

Picture Credit : Google