Perhaps the simplest technique to measuring a beach profile is known as the Emery board method, developed by a famous coastal
scientist named K.O. Emery. As depicted in Figure 3 (from Komar, 1998), the apparatus consists of two stakes connected by a rope
of known length (5m or 10m). This length sets the measurement interval for individual data points along the profile. Each stake has
a measurement scale which runs from 0 at the top, down to the bottom of the stake. Either English or Metric units can be used,
although the scientific community is nearly completely converted to the metric system. If the beach is sloping downward toward the
sea, the observer sights across the top of the seaward board to the level of the horizon, and determines the distance (a) from the
top of the landward board to the sightline. If the beach is locally sloping upward in the offshore direction, then (a) is measured on
the seaward board and the sighting is with the horizon over the top of the landward board. In either case, the measured distance (a)
is equal to the distance (b) that the beach has either dropped or risen within the horizontal distance between the boards (the rope
length). (Komar, 1998) This approach may seem simple, but it provides reasonably accurate measurements of beach profiles. It also
has the advantages of light, inexpensive, equipment, which can be easily carried to distant survey sights, for very rapid surveys.
Some success has been achieved in developing vehicles that can obtain beach profiles that extend across the entire nearshore and
into deeper water. The "surf rover" consists of two tractors which move a steel frame through the water. Mounted upon the steel
frame are instruments which record the vertical and horizontal positions of the rover. Another interesting device is the Coastal
Research Amphibious Buggy (CRAB), shown in Figure 4, which stands over 30 feet tall and can survey the surf zone to water depths
of approximately 9 meters.
บางทีเทคนิคง่ายที่สุดที่จะวัดโปรไฟล์ของชายหาดเรียกว่ากากกะรุนบอร์ดวิธีพัฒนาโดยนักวิทยาศาสตร์ที่มีชื่อเสียงชายฝั่ง
ชื่อ k.o. เอเมอรี ตามที่ปรากฎในรูปที่ 3 ( จากโคมาร์ , 1998 ) , เครื่องมือประกอบด้วยสองอันเชื่อมต่อกันด้วยเชือก
รู้จักความยาว ( 5 เมตร หรือ 10 เมตร ) ความยาวชุดวัดช่วงสำหรับแต่ละจุดข้อมูลตามรายละเอียดที่ แต่ละเดิมพันได้
a measurement scale which runs from 0 at the top, down to the bottom of the stake. Either English or Metric units can be used,
although the scientific community is nearly completely converted to the metric system. If the beach is sloping downward toward the
sea, the observer sights across the top of the seaward board to the level of the horizon, and determines the distance (a) from the
top of the landward board to the sightline. If the beach is locally sloping upward in the offshore direction, then (a) is measured on
the seaward board and the sighting is with the horizon over the top of the landward board. In either case, the measured distance (a)
is equal to the distance (b) that the beach has either dropped or risen within the horizontal distance between the boards (the rope
length). (Komar, 1998) This approach may seem simple, but it provides reasonably accurate measurements of beach profiles. It also
has the advantages of light, inexpensive, equipment, which can be easily carried to distant survey sights, for very rapid surveys.
Some success has been achieved in developing vehicles that can obtain beach profiles that extend across the entire nearshore and
into deeper water. The "surf rover" consists of two tractors which move a steel frame through the water. Mounted upon the steel
frame are instruments which record the vertical and horizontal positions of the rover. Another interesting device is the Coastal
Research Amphibious Buggy (CRAB), shown in Figure 4, which stands over 30 feet tall and can survey the surf zone to water depths
ประมาณ 9 เมตร
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