Short answer
Select MERIT DEM for projects demanding high vertical accuracy, and be aware that forest cover can significantly reduce the precision of global elevation models.
- Field
- Modelling
- Source
- International Journal of Geoinformatics (2023)
- Method
- Comparative accuracy assessment
- Sample
- 7757 GNSS points
- Evidence
- Strong effect
MERIT Digital Elevation Model demonstrates the highest vertical accuracy among tested global models, outperforming SRTM, NASA, and EarthEnv DEMs, particularly in non-forest and urban areas. This modelling research insight is drawn from a 2023 study published in International Journal of Geoinformatics. Using Comparative accuracy assessment with 7757 GNSS points, researchers explored how this design variable affects real-world outcomes. The key design takeaway: Select MERIT DEM for projects demanding high vertical accuracy, and be aware that forest cover can significantly reduce the precision of global elevation models.
MERIT DEM offers superior vertical accuracy (±2.668m RMSE) over other global models in diverse Malaysian terrains.
MERIT Digital Elevation Model demonstrates the highest vertical accuracy among tested global models, outperforming SRTM, NASA, and EarthEnv DEMs, particularly in non-forest and urban areas.
International Journal of Geoinformatics · 2023
Key Findings
- 01MERIT DEM exhibited the best vertical accuracy with an RMSE of ±2.668m, outperforming SRTM (±5.666m), NASA (±3.656m), and EarthEnv (±5.948m) when compared to GNSS data.
- 02All tested DEMs showed higher accuracy in non-forest areas, followed by urban areas, and the lowest accuracy in forest areas, indicating land cover significantly impacts DEM performance.
- 03The improvised DEMs showed only slight improvements over the original SRTM DEM.
Application
Design takeaway
Select MERIT DEM for projects demanding high vertical accuracy, and be aware that forest cover can significantly reduce the precision of global elevation models.
How to apply
When undertaking a design project that relies on elevation data (e.g., site suitability analysis, hydrological modelling, infrastructure planning), conduct a preliminary review of available global DEMs and select the one with the best-documented accuracy for the expected terrain and land cover conditions, prioritizing MERIT if high vertical accuracy is paramount.
Project actions
- 01When choosing a DEM for your design project, research its accuracy and limitations.
- 02Consider how different land cover types might affect the DEM's performance in your chosen study area.
Method & Evidence
Variables
Strengths & Limitations
Strengths
- +Utilized a large number of GNSS validation points.
- +Assessed accuracy across multiple distinct land cover types.
Limitations
The accuracy of DEMs can vary significantly depending on the terrain and vegetation. Results from one region may not directly apply to another.
Reliability & validity
The study's reliability is supported by the large sample size of GNSS points and the use of multiple high-resolution reference DEMs. Validity is enhanced by testing across diverse land cover types, providing a more comprehensive assessment of DEM performance.
Think critically
How might the differences in accuracy between these DEMs influence the outcome of a hydrological simulation or a landslide susceptibility analysis?
Design Principles
"Validate geospatial data sources against project-specific accuracy requirements and local ground truth where possible."
The selection of an appropriate Digital Elevation Model (DEM) is critical for the accuracy of geospatial analyses in fields like hydrology, geomorphology, and environmental planning. This research provides empirical data to guide designers and researchers in choosing the most reliable DEM for their specific project needs, especially when working with diverse land cover types.
What This Means for Your Design
This study found that the MERIT digital elevation model is the most accurate for measuring height compared to other free global models like SRTM, NASA, and EarthEnv. Its accuracy is best in open areas and worse in forests.
How to use in your project
- 1.Reference the study when justifying the choice of a specific Digital Elevation Model (DEM) for your design project, citing its accuracy metrics and suitability for your project's context.
- 2.Use the findings to explain potential limitations or sources of error in your design project if you are using a DEM that is not the most accurate.
Add to My Project
Quick Cite
Paragraph starter
The selection of a Digital Elevation Model (DEM) is a critical step in many design projects. Research indicates that MERIT DEM offers superior vertical accuracy (RMSE ±2.668m) compared to other widely used global models such as SRTM (RMSE ±5.666m), NASA (RMSE ±3.656m), and EarthEnv (RMSE ±5.948m), particularly in non-forest and urban environments. However, accuracy can degrade in forested areas, highlighting the importance of considering land cover when choosing a DEM for your design project.
Source
International Journal of Geoinformatics
Vertical Accuracy Assessment of Improvised Global Digital Elevation Models (MERIT, NASADEM, EarthEnv) Using GNSS and Airborne IFSAR DEM
journal · 2023
View sourceQuestions About This Research
- What does the research say about merit dem offers superior vertical accuracy (±2.668m rmse) over other global models in diverse malaysian terrains?
- Select MERIT DEM for projects demanding high vertical accuracy, and be aware that forest cover can significantly reduce the precision of global elevation models. Evidence: International Journal of Geoinformatics (2023).
- Why does "MERIT DEM offers superior vertical accuracy (±2.668m RMSE) over other global models in diverse Malaysian terrains." matter for design?
- The selection of an appropriate Digital Elevation Model (DEM) is critical for the accuracy of geospatial analyses in fields like hydrology, geomorphology, and environmental planning. This research provides empirical data to guide designers and researchers in choosing the most reliable DEM for their specific project needs, especially when working with diverse land cover types.
- How can designers apply this research?
- Select MERIT DEM for projects demanding high vertical accuracy, and be aware that forest cover can significantly reduce the precision of global elevation models.
- What were the main findings?
- MERIT DEM exhibited the best vertical accuracy with an RMSE of ±2.668m, outperforming SRTM (±5.666m), NASA (±3.656m), and EarthEnv (±5.948m) when compared to GNSS data.. All tested DEMs showed higher accuracy in non-forest areas, followed by urban areas, and the lowest accuracy in forest areas, indicating land cover significantly impacts DEM performance.. The improvised DEMs showed only slight improvements over the original SRTM DEM.
- What research method was used?
- Comparative accuracy assessment with 7757 GNSS points.
- How strong is the evidence?
- Evidence strength is rated Strong effect, based on a 2023 journal from International Journal of Geoinformatics.
- What should I do differently in my next project?
- When undertaking a design project that relies on elevation data (e.g., site suitability analysis, hydrological modelling, infrastructure planning), conduct a preliminary review of available global DEMs and select the one with the best-documented accuracy for the expected terrain and land cover conditions, prioritizing MERIT if high vertical accuracy is paramount.
- What are the limitations?
- The study was conducted in a specific geographic region (northern Peninsular Malaysia), and findings may vary in different geographical and geological settings. The assessment was limited to vertical accuracy.