Could you please list the top 15 engineering majors and a brief 2-3 sentence description of each major (e.g. what do they do/study, where do they work after college)?

Biomedical engineering
Important qualities in those who are considering a biomedical engineering degree are good analytical and math skills, as well as the ability to communicate effectively. Courses that benefit prospective biomedical engineers include chemistry, physics, biology and calculus, as well as drafting, mechanical drawing and computer programming.
( http://typesofengineeringdegrees.org/best-engineering-degree/#context/api/listings )

Computer engineering
Computer engineering is a field that combines aspects of computer science and electrical engineering. This being the case, people pursuing this major will often take some similar courses as those majoring in electrical engineering or computer science.
In this case, however, the focus will be more in the direction of developing computer hardware or software. They may be involved in creating new designs for personal computers or microprocessors. For this reason, they are often employed by companies that build computers as well as those that depend heavily on computer technology for their products.
( http://www.affordable-online-colleges.net/top-10-valuable-engineering-degrees-employers/ )
Most technological breakthroughs are coming in the area of software engineering and not computer hardware, so keep that in mind as well.
( http://typesofengineeringdegrees.org/highest-paid-engineering-jobs/#context/api/listings )

Software engineering
Software engineers are involved in the design and development of many types of software, including software for operating systems and network distribution, and software for compilers (which convert programs for execution on a computer). In programming, or coding, software engineers instruct a computer, line by line, how to perform a desired function. Software engineers must possess strong programming skills, but are often more concerned with developing algorithms and analyzing and solving programming problems than with actually writing code. There are different types of software engineers including computer applications software engineers, computer systems software engineers and systems software engineers.
( http://tryengineering.org/ask-expert/what-does-computer-software-engineer-do-could-you-give-me-description-field )
Course include computer fundamentals, data structures, principles of programming languages, software engineering, and computer architecture.
( http://study.com/articles/Become_a_Computer_Software_Engineer_Education_and_Career_Roadmap.html )

Environmental engineering
Because all levels of government must comply with environmental regulations, which in some areas are extremely restrictive, many municipalities hire environmental engineers to be sure that all regulations are met. Courses in biology, chemistry, physics, as well as algebra, trigonometry and calculus are beneficial for those considering environmental engineering as a career. Like all engineering positions, problem-solving skills are critical to becoming a successful environmental engineer. Other important qualities include good systems analysis abilities, communication skills and reading-comprehension. In addition, environmental engineers often must work with others to achieve common goals, so the ability to work as a team is also critical.
( http://typesofengineeringdegrees.org/best-engineering-degree/#context/api/listings )

Civil engineering
Civil engineers manage many different infrastructure projects, including building bridges, designing roads and upgrading levees or dams.
( http://typesofengineeringdegrees.org/best-engineering-degree/#context/api/listings )
Civil engineers have to keep this infrastructure running effectively and adapt it to meet challenges, such as population growth, climate change and natural disasters.There are many different specialisms within civil engineering, including environmental, structural, municipal, transport and geotechnical.
( https://www.theguardian.com/careers/what-does-civil-engineer-do )

Petroleum engineering
As oil and gas companies continue to seek convenient and cost-effective methods for extracting petroleum products, and drilling operations become more complex, the need for qualified petroleum engineers will grow over the next several years. Courses in mathematics, including algebra, trigonometry and calculus, along with biology, chemistry and physics are important for students working toward a petroleum engineer career. Important qualities include excellent analytical skills, creativity, strong math and problem solving skills. In addition, petroleum engineers must work well in teams as the position requires working with a variety of backgrounds and work habits.
( http://typesofengineeringdegrees.org/best-engineering-degree/#context/api/listings )

Sustainability Design & Engineering Degree
As the population grows, the demand for water and waste treatment also grows, requiring municipalities to design, build and maintain water and waste treatment systems. Coursework in statistics, engineering mechanics and physics are the best options to prepare for college level civil engineering studies. Important qualities in candidates include the ability to solve complex problems, excellent decision making, leadership abilities, and an understanding of complicated mathematics. Because only licensed civil engineers can sign off on infrastructure plans, they must be able to monitor and evaluate job site progress, making project management another critical skill. Civil engineers must report to other professionals, including architects, planners and administrators at state, county or city level, so writing and communication skills are also critical qualities.
( http://typesofengineeringdegrees.org/best-engineering-degree/#context/api/listings )

Electrical engineering
Electrical engineers study and apply the physics and mathematics of electricity, electronics, and electromagnetism to both large and small scale systems to process information and transmit energy. To do this, electrical engineers design computers, electronic devices, communication systems, test equipment, electric power networks, and improve systems through problem solving techniques.
( http://www.ee.calpoly.edu/prospective/electrical-engineering/ )
Because of the wide range of industries using electrical engineers, many engineers specialize in sub-discipline of electrical engineering. Common sub-disciplines include: PowerControl; Electronics; Microelectronics; Signal processing; Communication; Instrumentation; and Computers.
( http://www.learnhowtobecome.org/electrical-engineer/ )

Chemical engineering
Chemical engineers are typically employed in the areas of manufacturing and research. They work not only for chemical companies, but also work in the manufacturing of electronics, clothing, paper, medicine, and food to name just a few.
Chemical engineers can advance their careers from manufacturing plants to technical sales and company management. The market for chemical engineers is expected to be reasonably flat over the next few years. Job growth, however, in closely-related fields, such as biomedical engineering, is expected to be much faster than average job growth according to the US Department of Labor.
( http://typesofengineeringdegrees.org/highest-paid-engineering-jobs/#context/api/listings )

Materials engineering
Materials engineers work at developing and testing materials used in the production of industrial and consumer products, as well as working with metals and fabrics, and understanding the uses of each in consumer products.
( http://typesofengineeringdegrees.org/highest-paid-engineering-jobs/#context/api/listings )

This is a lesser known but still important type of engineering that includes characteristics of chemistry and physics. Materials science and engineering studies the properties and benefits of materials, especially those commonly used in industry, such as metals, plastic, textiles, rubber, glass and composites.
Materials engineers may also be involved in forensic engineering, which deals with the technical causes of product liability. Since this is something that is crucial for corporations to protect themselves against lawsuits, materials engineers are in high demand.
( http://www.affordable-online-colleges.net/top-10-valuable-engineering-degrees-employers/ )

Aerospace engineering
Depended upon to design aircraft, spacecraft, satellites, and missiles, aerospace engineers play a critical role in industrial development. According to the Bureau of Labor Statistics, manufacturers of aerospace products and parts are the biggest employers of aerospace engineers.
( https://www.sokanu.com/careers/aerospace-engineer/salary/ )

This field is mainly focused on research, design and testing of spacecrafts and aircrafts.
The field of aerospace engineering is roughly divided into two specialties. One is concerns with aircrafts, the other with spacecrafts that operate beyond the earth’s atmosphere. This is another field that is sure to expand in the future, as this type of technology is essential for so many industries, from transportation to the military.
( http://www.affordable-online-colleges.net/top-10-valuable-engineering-degrees-employers/ )

Nuclear engineering
Conducts research, designs, and monitors the operation and maintenance of nuclear reactors and power plant equipment. Although nuclear energy is not as widely discussed as petroleum, it remains a field where a great deal of work and research is conducted. Nuclear engineers may conduct research to develop nuclear based technology for the public or private sector.
They may also be involved in supervising operations to ensure that safety measures are properly in place. Nuclear engineers may even develop technologies used in the medical profession. ( http://www.affordable-online-colleges.net/top-10-valuable-engineering-degrees-employers/ )

Industrial engineering
Industrial engineering is one of the specialties of engineering that deals as much with people and organizations as it does with technology. This field is concerned with finding the most efficient and profitable systems and processes that can be best implemented by businesses and other organizations.
Industrial engineering connects several different disciplines, including management sciences, ergonomics, safety engineering and various social sciences. This is a degree that could prepare one for jobs in many different careers, including health care, finance or any organization looking to optimize its operations.
( http://www.affordable-online-colleges.net/top-10-valuable-engineering-degrees-employers/ )

Automotive engineering
Automotive engineering is one of the most exciting, challenging and rewarding careers. Whenever a customer drives a new vehicle off a dealership lot, he or she is taking with them the technical expertise of many engineers, but in particular, the automotive engineer.
Automotive engineers research, design and develop vehicles and their subsystems. Automotive engineers are concerned with the development of passenger cars, trucks, buses, motorcycles or off-road vehicles. They do one or more of the following: Design new products or modify existing ones; Troubleshoot and solve engineering problems;and Plan and design manufacturing processes. ( http://educatingengineers.com/careers/automotive-engineer )

Agricultural engineering
Agricultural engineering is also known as biological engineering, and it covers subjects from aquaculture (raising food sources that thrive in water), to land farming and forestry. These engineers also develop biofuels, plan animal environments, and find better food processing methods. Often they work in offices, but they are also outdoors and traveling to worksites where they oversee equipment function in agricultural settings, and assure that government regulations are met.( http://educatingengineers.com/career-specialties )