Thursday, July 9, 2026

Module 2 - Lidar

 

Figure 1 - Forest Analysis Part 1


Figure 2- Forest Analysis Part 2


 

This week’s lab represented a decent challenge for me! Technology was not cooperating, but overall, with proper troubleshooting, I was able to overcome and complete the assignment.

We conducted a LiDAR‑based forest analysis in Virginia to better understand canopy structure, terrain, and vegetation patterns relevant to forest management. We began by downloading and converting the Virginia LiDAR tile into an uncompressed LAS dataset, then explored the point cloud in a 3D local scene to observe landscape form, topography, and vegetation distribution. Using ground and non‑ground returns, we generated a DEM and DSM and subtracted them to estimate tree height across the study area. We evaluated height accuracy, identified outliers, and interpreted negative values in relation to roads and clearings. To assess biomass‑related canopy density, we converted LiDAR classes to multipoint features, rasterized them, and calculated vegetation to total return ratios to produce a canopy density surface. We then visualized height distribution with a histogram and created a series of maps to illustrate forest structure, highlight man‑made features, and support forestry applications such as biomass estimation, forest health assessment, and terrain‑based planning.


Friday, July 3, 2026

Module 1 - Crime Analysis

 



Image 1. Grid Overlay Hotspot Mapping


Image 2. Kernel Density Hotspot Analysis


Image 3. Local Moran's Hotspot Mapping

This first lab used our GIS skills to map crime incidences in both Washington and Chicago. In the last part of the lab, we explored three different techniques, Grid Overlay, Kernel Density, and Local Moran’s I hotspot mapping, to analyze which would be most efficient in predicting future crime from the perspective of a police department allocating resources.

To complete this analysis, I created three different hotspot maps using the 2017 homicide data for Chicago. I began with the grid‑based hotspot method by joining the homicide points to the half‑mile grid cells, selecting only the cells with at least one homicide, and then identifying the top twenty percent with the highest counts. I dissolved these selected cells into a single polygon to represent the grid‑based hotspot. Next, I created a kernel density hotspot by running the Kernel Density tool with the appropriate parameters for Chicago, adjusting the symbology to isolate values at or above three times the mean, reclassifying the raster into two classes, converting it to polygons, and selecting only the highest‑density areas. For the Local Moran’s I hotspot, I joined the homicide data to the census tracts, calculated homicide rates per one thousand housing units, and ran the Local Moran’s I tool to identify statistically significant high‑high clusters. I selected those clusters and dissolved them into a single boundary. These three hotspot methods provided different outlines of where homicides were concentrated in 2017, which I later compared to the 2018 homicide locations to evaluate how well each method predicted future crime.

The Local Moran’s hotspot would not be a great future predictor because, although it has a high number of 2018 homicides, this occurred over a very large area of 52.67 square miles. This is too broad and unable to pinpoint resource allocation accurately.

The Grid Overlay and Kernel Density data are relatively similar, with smaller areas and a large number of 2018 homicides. However, the density calculation is the dealbreaker here, with a high concentration of crime that is useful for a police chief to allocate his resources. Due to this, the Kernel Density hotspot analysis technique is the best to use as a production of future crime and allocation of resources.


Friday, May 1, 2026

Module 7- Neocartography

Figure 1 - View of South Florida Google Earth Tour
This week we used Google Earth Pro to create an interactive 3D map of South Florida. Google Earth Pro is widely used because it provides a simple way to view and distribute geographic information without requiring GIS software or training. Data in Google Earth can be saved and shared as KML or KMZ files, which are compatible with many GIS platforms. 

 In this lab, we first converted map layers from ArcGIS Pro into KMZ files, then loaded them into Google Earth Pro. We also add a legend as an image overlay and organize all layers into a folder. Much like ARC GIS Pro, one can edit layers, points and fonts, ect on Google Earth Pro.  Amongst the layers included population density data points and surface water. Then, we create a guided video tour in Google Earth Pro by adding placemarks for key locations in South Florida and the Tampa Bay region, including the Miami metropolitan area, Downtown Miami, Downtown Fort Lauderdale, Tampa Bay, St. Petersburg, and Downtown Tampa. Once all placemarks are created, we recorded the tour that flew to each location, adjusting layers, and exploring 3D buildings. 



Saturday, April 25, 2026

Module 6 - Isarithmic Mapping

 

Figure 1 - Isarithmic Map for Washington State Precipitation

In this lab, we explored how long‑term precipitation patterns in Washington are modeled using the PRISM interpolation method. The dataset, originally created by the USDA Service Center Agencies and published through the USDA Natural Resources Conservation Service in 2009, was downloaded from the USDA Geospatial Gateway and includes monthly and annual precipitation rasters. PRISM begins with 30 years of rainfall measurements collected from weather stations, then fills in the gaps between stations using interpolation. Because elevation strongly influences rainfall in Washington, PRISM incorporates a digital elevation model and a regression model that relates each station’s elevation to its precipitation values. These combined factors allow PRISM to estimate rainfall for 800‑meter grid cells, producing monthly surfaces that are summed into an annual precipitation map.

Throughout the lab, we worked extensively with continuous raster data and learned how to apply continuous tone symbology to represent smooth, gradual changes in precipitation. We also used legend‑editing tools to create clear, appropriate map legends and relied on the Spatial Analyst Extension to perform raster operations. Hypsometric tinting was implemented to highlight Washington’s terrain by assigning distinct color bands to elevation ranges, and hillshade relief was added to enhance the visual structure of the landscape. We used the Int tool to convert floating‑point rasters to integers, manually classified elevation data, and generated contours using both the Contour List tool and the Spatial Analyst Toolbar. Altogether, this lab strengthened our ability to symbolize continuous surfaces, interpret terrain, apply analytical tools, and clearly communicate the processes and outcomes involved in building a complete isarithmic map.

Sunday, April 19, 2026

Module 5 - Choropleth and Proportional Symbol Mapping


Figure 5 -  Map of European Wine Consumption


 For this project, the Albers projection was used because it preserves area accurately, which is essential for choropleth mapping. Since population density depends on the size of each region, an equal‑area projection prevents misleading distortions. Mapping population density instead of raw population counts also ensures the data is standardized and comparable across countries of different sizes.

A neutral tan color scheme was chosen to represent land, with darker shades showing higher population density. This palette is easy to interpret and avoids overwhelming the reader. Five classes were used to keep the map readable, and the data was classified using Natural Breaks because it best reflected the natural distribution of the dataset. Quantile classification was avoided because it would have grouped very different values together and misrepresented the data.

Wine consumption was displayed using red circles, which stand out clearly against the tan land and blue ocean. The data did not need normalization because population density was already calculated using area. SQL queries were used to filter and manipulate the dataset, allowing for cleaner data presentation and more precise symbol placement.

Graduated symbols were chosen over proportional symbols because they were more user‑friendly and communicated the ranges more clearly in the legend. Although proportional symbols are truest to the raw data, they made it harder to distinguish outliers like Vatican City and were less intuitive for readers. Flannery Compensation was not used; even if proportional symbols had been chosen, it would have exaggerated the Vatican outlier, caused symbol overlap in Europe’s dense geography, and made the legend harder to interpret.

Throughout the project, careful attention was given to cartographic design principles: selecting an appropriate color scheme, choosing a meaningful classification method, creating a clear and accurate legend, using effective thematic symbols, and compiling the final map in a way that communicates the data honestly and clearly. Including the projection information on the map reinforces that the spatial representation is accurate and that the data is being presented faithfully.

Saturday, April 11, 2026

Module 4 - Data Classification


In this week's lab, we worked with four common data classification methods, Equal Interval, Quantile, Standard Deviation, and Natural Breaks, to see how each one displays spatial data differently. Using ArcGIS Pro, we created a map layout with four data frames and symbolized each one using graduated colors to make the patterns easier to understand. We also practiced normalizing data, saving custom color schemes, and applying cartographic design principles to produce clear, readable maps. After comparing the classification methods, I evaluated which ones work best for different audiences and which data presentation approach most accurately represents the distribution of senior citizens in Miami‑Dade County.

 Then, two maps were generated using the different methods. he four classification methods each display the senior population data differently and reveal different patterns.

Equal Interval divides the data range into evenly sized classes, which is simple to read but often hides variation, especially after normalization, because most values get compressed into similar categories.

Quantile places the same number of features in each class, preventing empty categories but sometimes splitting similar values or grouping very different ones, which can distort the true differences.

Standard Deviation highlights how far values deviate from the mean, making it excellent for identifying unusually high or low concentrations of seniors, though it becomes less meaningful when the data is not normally distributed or when most values cluster near the average.

Natural Breaks finds the most meaningful clusters in the data, revealing the underlying structure, but the irregular class ranges make comparisons across datasets difficult.

For audiences who need to take action, such as planning senior services, the Standard Deviation method is the most useful because it clearly identifies areas with unusually high concentrations of seniors. For a casual viewer who just wants a general sense of the distribution, Natural Breaks is more intuitive and visually clear.

When presenting this information to Miami‑Dade County Commissioners, the population count normalized by area is the most accurate way to show where seniors actually live. Percentages can be misleading because small populations can appear disproportionately high, and equal percentages can represent very different numbers of people. Normalizing by square miles avoids distortions caused by varying tract sizes and provides a clearer picture of where services are most needed.


Figure 1- Normalized Data
Figure 2 - Data in Percentages 


Sunday, March 29, 2026

Module 3 - Cartographic Design

 


Figure - Map of Schools in Ward 7


This week, we used Gestalt’s Principles of Organization along with the other cartographic design principles we have learned so far in the course to create a map showing the locations of schools in Ward 7. The main map displayed this information along with general contextual features such as roads, highways, parks, and other environmental elements. Additionally, there was an inset map to show where Ward 7 is located in the context of Washington, D.C., and the surrounding areas. In our map, we had to demonstrate hierarchy, use contrast to show the relative importance of features, apply figure, ground principles to make certain features appear closer to the viewer, and accomplish all of this while maintaining a balanced, harmonious map that effectively communicates its purpose to the end reader.

Different tools were used, such as the clipping tool to select only the schools within the Ward 7 boundary. We also referred back to last week’s lab, where we practiced labeling. In this lab, we labeled neighborhoods, road systems, and the Anacostia River. To make the map more visually engaging, I took an additional step and learned how to convert labels to graphics, particularly useful for creating the shield symbols commonly used for different road and highway systems.

Since there were so many principles to remember, along with the challenge of using ArcGIS Pro, which can be tricky, I decided to tackle all of the labeling first. I fine‑tuned the labels and placed them exactly where I wanted them before moving on to the other map elements, such as fonts, sizing, and layout adjustments. It took some time, but breaking the project into these separate tasks made the overall process far less daunting.


Here are some of my design decisions and the reasoning behind them. 

In designing my map of schools in Ward 7, I focused heavily on visual hierarchy, contrast, figure ground, and balance. To establish hierarchy, I used different‑sized pushpin symbols for the schools so viewers could easily distinguish elementary, middle, and high schools. Their dark red color helped them stand out as the most important features. For the roads and highways, I used standard gallery symbols but adjusted line thicknesses to show their relative importance without overwhelming the map.

I also applied hierarchy through typography. The title used the largest font, while elements like the north arrow and scale bar were kept subtle. Although I wanted a larger font for the school list, space limitations required me to keep it at 11‑point.

To create contrast, I relied on both color and symbol differences. The school symbols were dark and bold, while the ward boundary was intentionally much lighter than its surroundings to highlight the area of interest. I used the same approach in the inset map, making Ward 7 even lighter so it remained visible at a smaller scale. For labels, I used Corbel and Tahoma in medium gray, readable but not overpowering and used bold or italic styles only when according to cartographic principles.

 I made Ward 7 noticeably lighter than the surrounding areas so it would visually “pop” forward. The rest of the map used a cohesive, neutral palette of beiges and grays to keep the focus on the schools and major features.

Balancing the layout required some trial and error. Since heavy elements at the top can make a map feel top‑heavy, I placed the school list at the bottom. Although the legend and school list on the right side made the layout slightly right‑heavy, the bold title and inset map on the left helped counterbalance this. I also made use of the natural triangular spaces created by the map extent to place elements efficiently.

Along the way, I refined several technical details: reorganizing the street drawing order so major roads weren’t covered, experimenting with gradient strokes to add subtle depth to the county layer, converting highway labels to graphics for easier editing, and using 75% transparency behind the school list so it wouldn’t block the map beneath it.

Overall, these choices helped create a map that is visually clear, balanced, and easy for viewers to interpret.


Module 2 - Lidar

  Figure 1 - Forest Analysis Part 1 Figure 2- Forest Analysis Part 2   This week’s lab represented a decent challenge for me! Technology w...