Dr. SaMeH S. Ahmed

Civil and Environmental Engineering Department

The ozone hole


The ozone hole



The discovery of the Antarctic "ozone hole" by British Antarctic Survey scientists FarmanGardiner and Shanklin (announced in a paper in Nature in May 1985) came as a shock to the scientific community, because the observed decline in polar ozone was far larger than anyone had anticipated Satellite measurements showing massive depletion of ozone around the south pole were becoming available at the same time. However, these were initially rejected as unreasonable by data quality control algorithms (they were filtered out as errors since the values were unexpectedly low); the ozone hole was detected only in satellite data when the raw data was reprocessed following evidence of ozone depletion in in situ observations. When the software was rerun without the flags, the ozone hole was seen as far back as 1976.]

Susan Solomon, an atmospheric chemist at the National Oceanic and Atmospheric Administration (NOAA), proposed that chemical reactions on polar stratospheric clouds (PSCs) in the cold Antarctic stratosphere caused a massive, though localized and seasonal, increase in the amount of chlorine present in active, ozone-destroying forms. The polar stratospheric clouds in Antarctica are only formed when there are very low temperatures, as low as −80 °C, and early spring conditions. In such conditions the ice crystals of the cloud provide a suitable surface for conversion of unreactive chlorine compounds into reactive chlorine compounds which can deplete ozone easily.

Moreover the polar vortex formed over Antarctica is very tight and the reaction which occurs on the surface of the cloud crystals is far different from when it occurs in atmosphere. These conditions have led to ozone hole formation in Antarctica. This hypothesis was decisively confirmed, first by laboratory measurements and subsequently by direct measurements, from the ground and from high-altitude airplanes, of very high concentrations of chlorine monoxide (ClO) in the Antarctic stratosphere]

Alternative hypotheses, which had attributed the ozone hole to variations in solar UV radiation or to changes in atmospheric circulation patterns, were also tested and shown to be untenable.[citation needed]

Meanwhile, analysis of ozone measurements from the worldwide network of ground-based Dobson spectrophotometers led an international panel to conclude that the ozone layer was in fact being depleted, at all latitudes outside of the tropics These trends were confirmed by satellite measurements. As a consequence, the major halocarbon producing nations agreed to phase out production of CFCs, halons, and related compounds, a process that was completed in 1996.

Since 1981 the United Nations Environment Programme, under the auspices of the World Meteorological Organization, has sponsored a series of technical reports on the Scientific Assessment of Ozone Depletion, based on satellite measurements. The 2007 report showed that the hole in the ozone layer was recovering and the smallest it had been for about a decade.The  2010 report found that "Over the past decade, global ozone and ozone in the Arctic and Antarctic regions is no longer decreasing but is not yet increasing... the ozone layer outside the Polar regions is projected to recover to its pre-1980 levels some time before the middle of this century... In contrast, the springtime ozone hole over the Antarctic is expected to recover much later."]

The hole in the Earth’s ozone layer over the South Pole has affected atmospheric circulation in the Southern Hemisphere all the way to the equator. The ozone hole has influenced atmospheric circulation all the way to the tropics and increased rainfall at low, subtropical latitudes in the Southern Hemisphere.

The Best Book

Prayer Times

Click here




Office hours

Sunday:      10-1

Monday:      12-1

Wednesday: 10-11

You are welcome to contact me by at any time

You  may also contact me via WhatsApp group

Ext. 2524

Time Table 2018-19S


Civil Eng. Students


DON'T miss!

Love your department and be proud of your field of study

As we approaching the second midterm exams..  Get ready and remember our offices are open to answer you . do not hesitate to .contact me if you have difficulties

For CE 370 students : Your second midterm exam will be on Wednesday 27 March 2019. In the surveying lab

Good Luck


Announcements


My Dear Students

Please visit the  announcement box for the relevant course and make sure that you can download and upload easily, otherwise

.contact me  to sort it out

There will be an orientation session in the midell of this term to help you select your track in Civil and Environmental Engineering

Special Event

Special Issue

Electrical Power Resources: Coal versus Renewable Energy



Published Online on January 2016


Mining Engineering


Mining engineering is an engineering discipline that involves practice, theory, science, technology, and the application of extracting and processing minerals from a naturally occurring environment. Mining engineering also includes processing minerals for additional value.

Environmental Engineering


Environmental engineers are the technical professionals who identify and design solutions for    environmental problems. Environmental engineers provide safe drinking water, treat and properly dispose of wastes, maintain air quality, control water pollution, and remediate sites contaminated due to spills or improper disposal of hazardous substances. They monitor the quality of the air, water, and land. And, they develop new and improved means to protect the environment.

Proverb

Actions speak louder than words

Tawasl


College of Eng. MU

http://mu.edu.sa/ar


Univeristies

Universities I've worked in


Assuit University (Home University), Egypt


Imperial College, London, UK


Faculty of Engineering, Al-Mergeb University, Libya


King Saud University, KSA

,Majmaah University


Majmaah University has a very nice web page that provide  all information regarding deanships, colleges, activities,  campuses and many others. Search your request in
http://mu.edu.sa/en

Also visit

My Academic Pages

https://www.researchgate.net/profile/Sameh_Ahemd

and give me


Think


??

Sports

Ahly vs Zamalek, 30 March 2019

Africa Nation Cup, June 2019


Course 2018/19-2


  1. Surveying 1 CE 370
  2. Surveying II  CE 371
  3. Senior Design II  (round 6) CE 499




The Rules of Life

Rule #1


Latest

Member of the Editorial Board: " Journal of Water Resources and Ocean Sciences"  2013 till now

https://www.researchgate.net/profile/Sameh_Ahmed5/?ev=hdr_xprf

Participating in The Third International Conference on Water, Energy and Environment,(ICWEE) 2019 - American University of Sharjah, UAE 26-28 March 2019 with a Paper and Poster

New article


Coming soon



2nd Midterm Exams on 3/4/2019

Student Conference



Participation  in the 6Th Student Conference

With a paper and oral presentation

From the Senior Design Project CE499 -35

See inside, the paper, and presentation

CE 370 Course

Surveying I

2018-2019S




Power point


Sheets


Lecture notes
15

3-4-2019

:Second Midterm Exam



Results


Model Answer
Inside, please follow

Working  marks is available -Click on Surveying I

CE 371 Course

Surveying II

2018-2019-2




Lectures





First midterm exam


Lab


Results

See Inside

Working marks out of 60 is  available- Click on Surveying 2

CE 474 Course

Photogrammetry

2018-2019-1



Available 0-1-2-3-4 Power point

Available

Quizzes 2 and 3 with model Answer

Quizzes
Available Chapter 1,2,3,4,5 Lecture notes

Report 1  Cameras Report

Y

60 marks Exams

See Inside

Student Performance Records


CE 499 Course

Senior Design 2


Second Best paper from Senior Design Projects in 2015

Paper title:

Evaluation of Groundwater Quality Parameters using Multivariate Statistics- a case Study of Majmaah, KSA

Students:

Abdullah A. Alzeer

Husam K. Almubark

Maijd M. Almotairi

Engineering Practice


A must for Engineer

Useful Links

Google

See what can you get from Google!! more than translation and locations

http://www.googlealert.com/

http://blogsearch.google.com/

http://books.google.com/

http://earth.google.com/

http://finance.google.com/finance


?What is your opinion

Email me in:  [email protected]


Saudi Vision 2030

Sustainability

Learn more about it


Riyadh Metro

A job opportunity 

Safe Fly


Surveying 2-19-3

JEAS

Conversion-Hegira to AD

Conversion


SDL

Saudi Digital Library

Research-gate

Visit me in RG

Success


Contact me

Mobile: 00966598311652

[email protected]

Civil and Environmental Engineering Department
College of Engineering, Majmaah University
Majmaah, P.O. 66, 11952, KSA

Thank you

خالص شكري وتقديري

إحصائية الموقع

عدد الصفحات: 2066

البحوث والمحاضرات: 2046

الزيارات: 71559