THE IMPACT OF SEA LEVEL RISE ON GEODETIC VERTICAL DATUM OF

PENINSULAR MALAYSIA AUTHORS:

A. H. M. Din, I. C. Abazu, M. F. Pa’suya, K. M. Omar and A. I. A. Hamid

ISAAC CHIDI ABAZU | GEOMATIC ENGINEERING | UTM

PRESENTER:

International Conference onGeomatics & Geospatial

Technology 2016

OUTLINE OF PRESENTATION

INTRODUCTION STUDY APPROACH RESULTS & DISCUSSION CONCLUSION

INTRODUCTION

(Nicholls et al., 2007)

INTRODUCTION

IPCC – A rise of just 20 centimetres, could result in the displacement of more than 300 million people.

(AVISO Research Team, 2012)

INTRODUCTION

Peninsular Malaysia Tide Gauge Station Distribution

1983 – Determination of precise MSL

called the Tidal Observation Network

(TON) by DSMM involving 12 tide gauge

observations.

Port Kelang Tide Gauge –Peninsular

Malaysia Geodetic Vertical Datum

(PMGVD).

PMGVD based on 10 years (1984 – 1993)

of tidal observations at Port Kelang.

MSL at 3.624m above zero tide gauge as

the reference level was adopted

STUDY APPROACH

Tide Gauge Station Setup

1. Tidal Data

UTM-Geomatic Innovations Research Group

STUDY APPROACH

Satellite Altimetry Concept

2. Satellite Altimeter Data (RADS)

STUDY APPROACH

1. Tidal DataSea Level Rise Rate: Jan. 1984 – Dec. 2015 (32 years).

Sea Level Magnitude: Subtracting yearly mean of 2015 from that of 1984.Tidal Average Difference at Port Kelang.

TOPEX, Jason-1, Jason-2, ERS-1, ERS-2, EnviSat, CryoSat-2 and Saral/Altika.

Sea Level Rise Rate from the SLA Between Jan. 1993 – Dec. 2015 (23 years) using Robust Fit Analysis.

Sea Level Magnitude: Subtracting yearly mean of 1993 from that of 2015.

2. Satellite Altimeter Data

RESULTS & DISCUSSIONSea Sea Level Rise Rate from Tide Gauges

Location Period Sea Level Rate (mm/yr)

Pulau Langkawi

1986 – 2015 3.35 ± 0.43

Pulau Pinang 1985 – 2015 3.25 ± 0.39

Lumut 1984 – 2015 2.70 ± 0.35

Port Kelang 1984 – 2015 2.35 ± 0.40

Tanjung Keling

1984 – 2015 2.44 ± 0.35

Kukup 1986 – 2015 3.60 ± 0.29

Johor Bahru 1984 – 2015 3.58 ± 0.24

Average 3.04 ± 0.35

Geting 1987 – 2015 3.62 ± 0.34

Cendering 1984 – 2015 3.43 ± 0.26

Tanjung Gelang

1984 – 2015 3.27 ± 0.22

Pulau Tioman 1986 – 2015 3.03 ± 0.25

Tanjung Sedili 1987 – 2015 2.55 ± 0.27

Average 3.18 ± 0.27

Total Average 3.11 ± 0.31

Geting with 3.62 ±0.34 mm/yr experienced the highest sea level rate by robust fit regression.

Port Kelang experienced the lowest rate at 2.35 ±0.40 mm/yr by robust fit regression.

The range of sea level rate by robust fit regression is from 2.35 ±0.40 mm/yr to 3.60 ±0.29 mm/yr.

The average relative sea level rate for Peninsular Malaysia calculated by robust fit regression yielded 3.11 ±0.31 mm/yr

RESULTS & DISCUSSION

Sea Sea Level Rise Rate from Tide Gauges

RESULTS & DISCUSSIONSea Sea Level Rise Magnitude from Tide Gauges

Location Time RangeYearly Mean

Sea Level Value (m)

Magnitude of SLR (m)

Cendering 1985 – 2015 2.187 – 2.279 0.092Kukup 1986 – 2015 3.987 – 4.073 0.086Pulau Langkawi

1986 – 2015 2.182 – 2.256 0.074

Geting 1987 – 2015 2.252 – 2.326 0.074Johor Bahru* 1984 – 2013 2.852 – 2.915 0.063Pulau Pinang 1986 – 2015 2.658 – 2.716 0.058Pulau Tioman 1986 – 2015 2.812 – 2.866 0.053Tanjung Gelang

1984 – 2015 2.804 – 2.840 0.035

Tanjung Sedili 1987 – 2015 2.373 – 2.400 0.028Lumut 1985 – 2015 2.206 – 2.224 0.017Port Kelang 1984 – 2015 3.678 – 3.680 0.002Tanjung Keling

1985 – 2015 2.868 – 2.866 -0.001

Minimum -0.001 Maximum 0.092

Total Average 0.048

The smallest magnitude of -0.001m occurred at Tanjung Keling.

The largest magnitude of 0.092m occurred at Cendering.

Inconsistent magnitude of sea level rise along the coast of Peninsular Malaysia.

The short term circulation dynamics don’t average out & this causes the MSL to have a disturbed annual cycle with lots of higher harmonics.

Influence of the “very strong” El Niño in 2015/2016 (ONI, 2016).

RESULTS & DISCUSSION

Tidal Average of 32 Years (1984 – 2015) Difference Tidal Average of 10 Years (1984 – 1993) for PMGVD

Port Kelang

The computed MSL B (3.651m) from 32 years data shows the MSL is increasing.

The magnitude shows that the size of the movement of MSL B from MSL A is 27mm

Long-term effect it has on the Peninsular Malaysia geodetic vertical datum since Port Kelang is the adopted local vertical datum origin for Peninsular Malaysia.

Year Mean (m)

Year Mean (m)

Year Mean

(m)1984 3.68 1995 3.66 2006 3.611985 3.65 1996 3.67 2007 3.641986 3.61 1997 3.54 2008 3.661987 3.58 1998 3.65 2009 3.711988 3.65 1999 3.69 2010 3.741989 3.64 2000 3.74 2011 3.671990 3.61 2001 3.70 2012 3.731991 3.58 2002 3.61 2013 3.741992 3.61 2003 3.64 2014 3.661993 3.62 2004 3.63 2015 3.681994 3.58 2005 3.65

MSL A (1984 to 1993) = 3.624m (PMGVD)MSL B (1984 to 2015) = 3.651mMagnitude (MSL B – MSL A) = 0.027m

RESULTS & DISCUSSION

Sea Level Variation Using Satellite Altimeter from 1993 to 2015 (23 Years)

The rate of sea level varies and gradually increases from west to east of Peninsular Malaysia.

The Malacca Straits has lower rate of absolute sea level rise trend compared to South China Sea.

Malacca Straits has an average of 3.14 ±0.12 mm/yr, while South China Sea is estimated at 3.85 ±0.05 mm/yr.

Depth and shape of the Malacca Straits is shallow and rather narrow. Besides, the tides or water flows mainly enters from one side of the strait and are influenced by the geometrical changes from the north-west to south-east and the tiny islands at the south-east end.

South China Sea

Malacca Straits

RESULTS & DISCUSSION

Sea Level Magnitude Using Satellite Altimeter from 1993 to 2015 (23 Years)

Yearly sea level anomaly in 2015 was subtracted with yearly sea level anomaly in 1993 to quantify the sea level rise magnitude

The magnitude of sea level rise is higher in South China Sea compared to Malacca Straits

The sea level rise magnitude is at range of 4cm to 10cm for South China Sea and -15cm to 6cm for Malacca Straits.

South China Sea

Malacca Straits

RESULTS & DISCUSSION

Sea Level Magnitude Using Satellite Altimeter for 1993 & 2015

The sea level anomaly magnitude in Malacca Straits is higher than that of the South China Sea

South China Sea

Malacca Straits

South China Sea

Malacca Straits

RESULTS & DISCUSSIONMSL Height Variation at Port Kelang Benchmark

The height of the tide gauge bench mark B0169 was fixed relative to the MSL from the Port Kelang tide gauge zero.

Magnitude of MSL change by comparing old MSL (3.864m) at B0169 spanning 1984 to 1993 to a new MSL (3.837m) spanning 1984 to 2015 tidal data.

The resultant difference of -0.027m indicates the upward movement of the MSL. A long-term change in the MSL will result in a change in the geodetic vertical datum

at the Bench mark.

South China Sea

Modified from PSMSL (2016)

CONCLUSION

Sea level is rising and varying from place to place over the peninsular Malaysian seas, increasing from west coast to east.

The sea level rise signals are consistent from both tidal and altimeter data.

The Satellite Altimeter average sea level rate calculated by robust fit regression was estimated at 3.11 ±0.31 mm/yr (South China Sea) and 3.50 +/- 0.09 mm/yr (Malacca Straits).

Sea level magnitude ranges from 0cm to 10cm over the most part of Peninsular Malaysian seas.

Sea level increase of about 27mm demonstrates an estimated long-term effect a change in MSL has on the geodetic vertical datum of Port Kelang tide gauge station.

ACKNOWLEGDEMENT

DSMM, TU Delft, NOAA, Altimetrics Llc and the Permanent Service for Mean Sea Level (PSMSL) –Altimetry and Tidal data.

Ministry of Higher Education (MOHE) for funding this project under the FRGS Fund, Vote Number R.J130000.7827.4F706

UTM, JOHOR.

THANK YOU

Isaac Chidi ABAZU –B.Tech, M.Sc.

Geomatic Innovations Research GroupFaculty of Geoinformation & Real Estate

Universiti Teknologi Malaysia.