diff --git a/js/id/actions/circularize.js b/js/id/actions/circularize.js
index d1c973723..10a8f0f7c 100644
--- a/js/id/actions/circularize.js
+++ b/js/id/actions/circularize.js
@@ -8,7 +8,7 @@ iD.actions.Circularize = function(wayId, projection, maxAngle) {
             points = nodes.map(function(n) { return projection(n.loc); }),
             keyPoints = keyNodes.map(function(n) { return projection(n.loc); }),
             centroid = d3.geom.polygon(points).centroid(),
-            radius = d3.median(points, function(p) { return iD.geo.dist(centroid, p); }),
+            radius = d3.median(points, function(p) { return iD.geo.euclideanDistance(centroid, p); }),
             sign = d3.geom.polygon(points).area() > 0 ? 1 : -1,
             ids;
 
@@ -44,7 +44,7 @@ iD.actions.Circularize = function(wayId, projection, maxAngle) {
             }
 
             // position this key node
-            distance = iD.geo.dist(centroid, keyPoints[i]);
+            distance = iD.geo.euclideanDistance(centroid, keyPoints[i]);
             keyPoints[i] = [
                 centroid[0] + (keyPoints[i][0] - centroid[0]) / distance * radius,
                 centroid[1] + (keyPoints[i][1] - centroid[1]) / distance * radius];
diff --git a/js/id/actions/orthogonalize.js b/js/id/actions/orthogonalize.js
index 6789768c8..d21cd5372 100644
--- a/js/id/actions/orthogonalize.js
+++ b/js/id/actions/orthogonalize.js
@@ -84,7 +84,7 @@ iD.actions.Orthogonalize = function(wayId, projection) {
                 p = subtractPoints(a, b),
                 q = subtractPoints(c, b);
 
-            var scale = 2*Math.min(iD.geo.dist(p, [0, 0]), iD.geo.dist(q, [0, 0]));
+            var scale = 2*Math.min(iD.geo.euclideanDistance(p, [0, 0]), iD.geo.euclideanDistance(q, [0, 0]));
             p = normalizePoint(p, 1.0);
             q = normalizePoint(q, 1.0);
 
diff --git a/js/id/actions/split.js b/js/id/actions/split.js
index 8875c1e1d..be1a9153f 100644
--- a/js/id/actions/split.js
+++ b/js/id/actions/split.js
@@ -44,7 +44,7 @@ iD.actions.Split = function(nodeId, newWayIds) {
                 return iD.util.wrap(index,nodes.length);
             }
             function _dist(nA, nB) {
-                return iD.geo.dist(graph.entity(nA).loc, graph.entity(nB).loc);
+                return iD.geo.sphericalDistance(graph.entity(nA).loc, graph.entity(nB).loc);
             }
 
             // calculate lengths
diff --git a/js/id/behavior/draw.js b/js/id/behavior/draw.js
index e202030a2..d305d944f 100644
--- a/js/id/behavior/draw.js
+++ b/js/id/behavior/draw.js
@@ -34,8 +34,8 @@ iD.behavior.Draw = function(context) {
 
         d3.select(window).on('mouseup.draw', function() {
             element.on('mousemove.draw', mousemove);
-            if (iD.geo.dist(pos, point()) < closeTolerance ||
-                (iD.geo.dist(pos, point()) < tolerance &&
+            if (iD.geo.euclideanDistance(pos, point()) < closeTolerance ||
+                (iD.geo.euclideanDistance(pos, point()) < tolerance &&
                 (+new Date() - time) < 500)) {
 
                 // Prevent a quick second click
diff --git a/js/id/geo.js b/js/id/geo.js
index ff6b060c8..3b901d263 100644
--- a/js/id/geo.js
+++ b/js/id/geo.js
@@ -10,17 +10,23 @@ iD.geo.interp = function(p1, p2, t) {
 };
 
 // http://jsperf.com/id-dist-optimization
-iD.geo.dist = function(a, b) {
+iD.geo.euclideanDistance = function(a, b) {
     var x = a[0] - b[0], y = a[1] - b[1];
     return Math.sqrt((x * x) + (y * y));
 };
+// Equirectangular approximation of spherical distances on Earth
+iD.geo.sphericalDistance = function(a, b) {
+    var x = Math.cos(a[1]*Math.PI/180) * (a[0] - b[0]),
+        y = a[1] - b[1];
+    return 6.3710E6 * Math.sqrt((x * x) + (y * y)) * Math.PI/180;
+};
 
 // Choose the edge with the minimal distance from `point` to its orthogonal
 // projection onto that edge, if such a projection exists, or the distance to
 // the closest vertex on that edge. Returns an object with the `index` of the
 // chosen edge, the chosen `loc` on that edge, and the `distance` to to it.
 iD.geo.chooseEdge = function(nodes, point, projection) {
-    var dist = iD.geo.dist,
+    var dist = iD.geo.euclideanDistance,
         points = nodes.map(function(n) { return projection(n.loc); }),
         min = Infinity,
         idx, loc;
diff --git a/js/id/operations/delete.js b/js/id/operations/delete.js
index c4863cdbd..d81d84a0d 100644
--- a/js/id/operations/delete.js
+++ b/js/id/operations/delete.js
@@ -27,8 +27,8 @@ iD.operations.Delete = function(selectedIDs, context) {
                 } else if (i === nodes.length - 1) {
                     i--;
                 } else {
-                    var a = iD.geo.dist(entity.loc, context.entity(nodes[i - 1]).loc),
-                        b = iD.geo.dist(entity.loc, context.entity(nodes[i + 1]).loc);
+                    var a = iD.geo.sphericalDistance(entity.loc, context.entity(nodes[i - 1]).loc),
+                        b = iD.geo.sphericalDistance(entity.loc, context.entity(nodes[i + 1]).loc);
                     i = a < b ? i - 1 : i + 1;
                 }
 
diff --git a/js/id/svg.js b/js/id/svg.js
index a74b56986..00e6a8c2b 100644
--- a/js/id/svg.js
+++ b/js/id/svg.js
@@ -63,7 +63,7 @@ iD.svg = {
                     b = [x, y];
 
                     if (a) {
-                        var span = iD.geo.dist(a, b) - offset;
+                        var span = iD.geo.euclideanDistance(a, b) - offset;
 
                         if (span >= 0) {
                             var angle = Math.atan2(b[1] - a[1], b[0] - a[0]),
diff --git a/js/id/svg/midpoints.js b/js/id/svg/midpoints.js
index 892efd141..55a069172 100644
--- a/js/id/svg/midpoints.js
+++ b/js/id/svg/midpoints.js
@@ -20,7 +20,7 @@ iD.svg.Midpoints = function(projection, context) {
                 // If neither of the nodes changed, no need to redraw midpoint
                 if (!midpoints[id] && (filter(a) || filter(b))) {
                     var loc = iD.geo.interp(a.loc, b.loc, 0.5);
-                    if (extent.intersects(loc) && iD.geo.dist(projection(a.loc), projection(b.loc)) > 40) {
+                    if (extent.intersects(loc) && iD.geo.euclideanDistance(projection(a.loc), projection(b.loc)) > 40) {
                         midpoints[id] = {
                             type: 'midpoint',
                             id: id,
diff --git a/test/spec/actions/circularize.js b/test/spec/actions/circularize.js
index 9456f109e..282310796 100644
--- a/test/spec/actions/circularize.js
+++ b/test/spec/actions/circularize.js
@@ -48,7 +48,7 @@ describe("iD.actions.Circularize", function () {
 
         graph = iD.actions.Circularize('-', projection)(graph);
 
-        expect(iD.geo.dist(graph.entity('d').loc, [2, -2])).to.be.lt(0.5);
+        expect(iD.geo.euclideanDistance(graph.entity('d').loc, [2, -2])).to.be.lt(0.5);
     });
 
     function angle(point1, point2, center) {
@@ -56,10 +56,10 @@ describe("iD.actions.Circularize", function () {
             vector2 = [point2[0] - center[0], point2[1] - center[1]],
             distance;
 
-        distance = iD.geo.dist(vector1, [0, 0]);
+        distance = iD.geo.euclideanDistance(vector1, [0, 0]);
         vector1 = [vector1[0] / distance, vector1[1] / distance];
 
-        distance = iD.geo.dist(vector2, [0, 0]);
+        distance = iD.geo.euclideanDistance(vector2, [0, 0]);
         vector2 = [vector2[0] / distance, vector2[1] / distance];
 
         return 180 / Math.PI * Math.acos(vector1[0] * vector2[0] + vector1[1] * vector2[1]);
diff --git a/test/spec/actions/orthogonalize.js b/test/spec/actions/orthogonalize.js
index 396403749..ed889bda0 100644
--- a/test/spec/actions/orthogonalize.js
+++ b/test/spec/actions/orthogonalize.js
@@ -97,12 +97,12 @@ describe("iD.actions.Orthogonalize", function () {
                     'd': iD.Node({id: 'd', loc: tests[i][3]}),
                     '-': iD.Way({id: '-', nodes: ['a', 'b', 'c', 'd', 'a']})
                 }),
-                initialWidth = iD.geo.dist(graph.entity('a').loc, graph.entity('b').loc),
+                initialWidth = iD.geo.sphericalDistance(graph.entity('a').loc, graph.entity('b').loc),
                 finalWidth;
 
             graph = iD.actions.Orthogonalize('-', projection)(graph);
 
-            finalWidth = iD.geo.dist(graph.entity('a').loc, graph.entity('b').loc);
+            finalWidth = iD.geo.sphericalDistance(graph.entity('a').loc, graph.entity('b').loc);
             expect(finalWidth / initialWidth).within(0.90, 1.10);
         }
     });
diff --git a/test/spec/geo.js b/test/spec/geo.js
index ba2f401a9..7592782b7 100644
--- a/test/spec/geo.js
+++ b/test/spec/geo.js
@@ -18,21 +18,49 @@ describe('iD.geo', function() {
         });
     });
 
-    describe('.dist', function() {
+    describe('.euclideanDistance', function() {
         it('distance between two same points is zero', function() {
             var a = [0, 0],
                 b = [0, 0];
-            expect(iD.geo.dist(a, b)).to.eql(0);
+            expect(iD.geo.euclideanDistance(a, b)).to.eql(0);
         });
         it('a straight 10 unit line is 10', function() {
             var a = [0, 0],
                 b = [10, 0];
-            expect(iD.geo.dist(a, b)).to.eql(10);
+            expect(iD.geo.euclideanDistance(a, b)).to.eql(10);
         });
         it('a pythagorean triangle is right', function() {
             var a = [0, 0],
                 b = [4, 3];
-            expect(iD.geo.dist(a, b)).to.eql(5);
+            expect(iD.geo.euclideanDistance(a, b)).to.eql(5);
+        });
+    });
+
+    describe('.sphericalDistance', function() {
+        it('distance between two same points is zero', function() {
+            var a = [0, 0],
+                b = [0, 0];
+            expect(iD.geo.sphericalDistance(a, b)).to.eql(0);
+        });
+        it('a straight 1 degree line at the equator is aproximately 111 km', function() {
+            var a = [0, 0],
+                b = [1, 0];
+            expect(iD.geo.sphericalDistance(a, b)).to.be.within(100E3,120E3);
+        });
+        it('a pythagorean triangle is right', function() {
+            var a = [0, 0],
+                b = [4, 3];
+            expect(iD.geo.sphericalDistance(a, b)).to.be.within(500E3,600E3);
+        });
+        it('east-west distances at high latitude are shorter', function() {
+            var a = [0, 60],
+                b = [1, 60];
+            expect(iD.geo.sphericalDistance(a, b)).to.be.within(50E3,60E3);
+        });
+        it('north-south distances at high latitude are not shorter', function() {
+            var a = [0, 60],
+                b = [0, 61];
+            expect(iD.geo.sphericalDistance(a, b)).to.be.within(100E3,120E3);
         });
     });