Climate effects from historical volcanic eruptions Research Paper

Climate effects from historical volcanic eruptions - Research Paper Example The change in climatic conditions as observed by the scientist was as a result of volcanic activity. The paper will explain the various climatic effects that resulted from volcanic eruption in the past1. The change was linked to the eruption of the Laki fissure system. Laki fissure system was a chain of volcanic activities that results to the movement of lava through several cracks in the ground rather than from a single point. The eruption happened in Iceland. The Laki eruptions took place in more than 8 months and produced about 14 km3 of basalt that was made up thin, black and fluid lava. The eruption also resulted to production of ash clouds that made their way into the stratosphere. The ash clouds formed a dense haze across Europe which resulted to blockage of the sun’s rays from reaching the ground. In addition to the ash, the eruptive clouds that came out of the fissures consisted mainly of high quantities of hydrogen chloride, sulfur dioxide and hydrogen Fluoride gases2. These gases combined with atmospheric water to produce acid rain that lead to death of livestock as well as destruction of vegetations and crops. The effect was however severe in Iceland where seventy five percent of the livestock and twenty five percent of the people died from the toxic impact of the volcanic activities. The impact of the eruption was also felt in places far away from Iceland. During the period the United States recorded low temperatures. In fact, the temperatures in the northern hemisphere decreased by over a degree Celsius. There are various reasons on how large volcanic eruption may have an impact on the global climate. Volcanic eruptions often produce large quantities of carbon dioxide, a gas that is associated with the green house effect. Carbon dioxide is known to trap gases that are been radiated form the surface of the earth forming an insulations around the earth. The green house impact is essential for human survival as it maintains the temperatures

The Value of Pair and Group Work for Second Language Learning Essay

The Value of Pair and Group Work for Second Language Learning - Essay Example But some teachers are not yet ready to change and accept change. Besides, they are unconvinced about the value of using pair and group work in the classroom environment. From another angle of view, the mindset of student community towards pedagogical innovation deeply influences its effectiveness in the classroom environment. This view has been supported in the work of Hinkel (2005, P. 141). The value of pair and group work in the classroom environment is that it helps learners gets enough opportunity to practice the language. For instance, pair and group work help the learners to have enough time for oral practice. Besides, less confident learners get exposure to put newly acquired language skills into practice. Pair and group work in classroom environment leads to less dependence on a teacher, helping and learning enhances language acquisition. Pair and group work change the traditional role of the individual teacher in the classroom environment. Group work is helpful for the learners to share their ideas with their peers. In addition, learning experience in classroom environment under the supervision of teacher enhances the learning process. Dividing the class into different groups consist of gifted, fast learners, average students and below average students is helpful for the student community to develop their language skills. Besides, pair and group work helps the teacher to provide individual attention to each and every student. Grouping the students by considering their ability or language proficiency is not democratic but it leads to the failure of classroom instruction on and tasks formulated by the teacher. This view has been supported in the work of Genesee (1994, p.186). The traditional mode of classroom instruction based on the teacher is not democratic. In this situation, the teacher is lecturing and the students are mere listeners.