More than 50% of all aquatic species were wiped out and eliminated many land animals and plants, most notably all the dinosaurs except for the birds. The causes include climate change which occurred due to volcanic floods in India as a consequence of a giant comet Collison in the Gulf of Mexico (Wake, D.B., Vredenburg, V.T. and wakelab, 2008). Evidence for this can be supported by the fact that Iridium a very rare element found on earth but commonly found in extra-terrestrial objects and a layer of iridium was found on the coast of Mexico. The crater in Mexico is similar in size to an object with a radius of 5km, which could have collided there (Reece,
The Pleistocene epoch occurred between 2.6 million years ago and 11700 years ago, and was the base of the Quaternary; the most recent period. The most recent ice age occurred during the Pleistocene epoch, with huge parts of the Earth’s landmasses being covered by glaciers. The Pleistocene did not consist of just one great ice age. Instead, it involved frequent fluctuations of warming and cooling of the Earth’s atmosphere. This included more than 30 changes between long glacial periods where much of the world’s temperate zones were covered by glaciers and brief warmer interglacial phases where some ice sheets retreated; much like what we are living in today (Holden, 2012).
While technology makes sea-level rise easier to observe, and some contributions to future sea-level rise can be predicted with increasing certainty, yet the ice sheets’ contribution cannot be wholly predicted. There is thus a risk that sea-level rise contributed by ice melting could be higher than the estimates provided by the IPCC. There is also, however, a possibility that the effect on sea level imposed by ice melting in Antarctica is minimal. Researches show that the East Antarctic ice sheet may thicken slowly in the future due to the increased snowfall. The increase in ice capacity in East Antarctica may cancel out the melting of ice cap in other parts of Antarctica, causing little overall melting.
A combination of climate change, pollution and search for natural resources is threatening the fragile species and ecosystems within the Arctic region. Over the last two centuries the world's global mean temperature has increased by 0.6 degrees, noting this continuous change in global temperatures is too accelerated for the natural environment to adapt to. Much of this change in global temperatures is the result of c02 emissions being released into the atmosphere. Currently, 80% of the world's growing energy demands are met by the burning of fossil fuels which emit astonishing amounts of c02 into our atmosphere (3). As the name suggests, climate change references the change of the climate, unfortunately this is not limited to the fragile systems of
For example, the planet has swung between cold glacial periods or "ice ages", and warm interglacial periods over the last few million years. Changes in the past can be explained by natural factors such as changes in the Earth 's orbit, in the sun 's intensity, in the amount of explosive volcanic activity, by changes to the surface of the Earth, and farther back in time, to the position of the continents. Of these, only changes in the sun’s intensity and volcanic activity are relevant on century timescales. However, today human activity has now become the main cause of recent climate change. The strong global warming observed since the mid-20th century has been
The consequences Global warming has led to that the sea level rise is accelerating, the number of large wildfires is growing, dangerous heat waves are becoming more common, extreme storm events are increasing in many areas and more severe droughts are occurring in others. It also causes many seasonal changes like longer winters and shorter summers. Animals and plants The increase in greenhouse gases is changing the climate faster than some living things may be able to adapt. Many species of animals and plants have already disappeared because of climate change. Global warming is causing a shift in the timing of natural events in the lives of animals.
Dynesius and Nilsson 1994) will include the alteration of vegetation that causes downstream habitat effects such as enlargement of floodplains, wetlands and riparian zones. It also causes the collapse of river to ocean estuaries as well as the collapse of river deltas (e.g. Rosenberg et al. 1997), that leads to the water mass loss in rivers, causing a decrease in the quality of the remaining water due to dilution issues of pollution. (NRC 1992, Gillilan and Brown 1997).
The world today has recorded a total of 5 main mass extinction events which are commonly known as the Big 5. A scientific journal (Benton & Harper, 2009) has stated that to classify an event as a mass extinction, it must meet the following criteria: a) Extinction percentage of animals and plants must be atleast 30% b) The event should happen in a short period of time c) The level of extinction should be higher than the background extinction level d) The extinction should happen across different regions e) The extinction consists of different species of living organisms Mass extinction is caused by major catastrophic events which are linked together directly and has the ability to wipe out living organisms off the face of the earth. This essay will cover on The
Natural Disaster What is natural disaster? How does it occur? How does natural disaster affects our life? Any phenomenon that happens in nature that can cause severe damage to our environment, economic losses and even death is known as a natural disaster. Natural disaster happens all over the world uncontrollably and causes loss in some way.