Insolation (Incoming Solar Radiation) is the amount of solar radiation incident on any surface – for our purposes, we will be comparing insolation levels on the surface of the Earth. The amount of insolation received at the surface of the Earth is controlled by the angle of the sun, the state of the atmosphere, altitude, and geographic location.
The values of solar insolation are commonly expressed in kWh/m 2/day. This is the amount of solar energy that strikes a square meter of the earth’s surface in a single day.
Insolation levels are used to determine what size solar collector is needed to efficiently provide adequate levels of hot water. Geographic locations with low insolation levels require larger collectors than locations with higher insolation levels.
For comparison, consider the average annual insolation levels of these two extreme locations:
*Oslo , Norway = 2.27 kWh/m 2/day (very low)
*Miami , Florida = 5.26 kWh/m 2/day (very high)
For more information on the science of solar insolation, refer to Wikipedia’s page http://en.wikipedia.org/wiki/Insolation.
| Region | State | City | Latitude | Longitude | Jan | Feb | Mar | Apr | May | June | Jul | Aug | Sept | Oct | Nov | Dec | YearAverage |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Africa | SL | freetown | 8 29' N | 13 14' W | 5.19 | 5.91 | 6.08 | 5.47 | 4.76 | 4.09 | 3.6 | 3.58 | 4.25 | 4.84 | 4.93 | 4.94 | 4.8 |
| Africa | SD | al khur-tum | 15 33' N | 32 32' E | 5.46 | 6.19 | 6.75 | 7.25 | 6.85 | 6.96 | 6.52 | 6.35 | 6.42 | 6.17 | 5.66 | 5.22 | 6.31 |
| Africa | NG | abuja | 9 12' N | 7 11' E | 5.57 | 6.33 | 6.22 | 6.1 | 5.89 | 5.47 | 4.92 | 4.65 | 5.12 | 5.82 | 5.81 | 5.42 | 5.61 |
| Africa | NE | niamey | 13 30' N | 2 12' W | 5.42 | 6.39 | 6.72 | 6.79 | 6.75 | 6.31 | 6.07 | 5.78 | 6.07 | 6.16 | 5.79 | 5.29 | 6.12 |
| Africa | MR | nouakchott | 17 45' N | 15 45' E | 5.31 | 6.21 | 6.8 | 7.54 | 7.57 | 7.63 | 7.2 | 6.9 | 6.78 | 6.34 | 5.49 | 4.88 | 6.55 |
| Africa | ML | bamako | 12 30' N | 7 54' E | 5.61 | 6.35 | 6.64 | 6.78 | 6.42 | 6.47 | 5.87 | 5.65 | 6.04 | 6.13 | 5.85 | 5.36 | 6.09 |
| Africa | LY | tarabulus | 32 54' N | 13 11' E | 3.1 | 4.03 | 5.19 | 6.48 | 6.89 | 7.77 | 8.11 | 7.45 | 6.12 | 4.58 | 3.35 | 2.76 | 5.48 |
| Africa | MA | rabat | 32 32' N | 9 17' W | 3.13 | 3.86 | 5.09 | 6.08 | 6.89 | 7.31 | 7.34 | 6.8 | 5.69 | 4.37 | 3.25 | 2.82 | 5.21 |
| Africa | LR | liberia | 6 30' N | 9 30' W | 5.43 | 5.72 | 5.59 | 5.31 | 5.11 | 4.61 | 4.25 | 4.19 | 4.67 | 5.13 | 5.24 | 5.2 | 5.03 |
| Africa | KE | nairobi | 1 16' S | 36 48' E | 6.05 | 6.24 | 6.07 | 5.7 | 5.42 | 5.14 | 4.88 | 5.09 | 5.78 | 6.03 | 5.48 | 5.6 | 5.62 |
| Africa | GN | conakry | 9 36' N | 13 36' E | 5.81 | 6.41 | 6.51 | 6.22 | 5.69 | 5.69 | 5.09 | 5.05 | 5.46 | 5.87 | 5.98 | 5.6 | 5.78 |
| Africa | GM | gambia | 13 28' N | 16 39' W | 5.01 | 5.93 | 6.67 | 6.92 | 6.72 | 6.06 | 5.48 | 5.09 | 5.3 | 5.67 | 5.36 | 4.95 | 5.76 |
| Africa | ET | addis abeba | 9 2' N | 38 42' E | 5.96 | 5.8 | 6.23 | 6.31 | 6.11 | 5.79 | 5.03 | 5 | 5.64 | 6.31 | 6.15 | 5.75 | 5.84 |
| Africa | GH | accra | 5 36` N | 0 12` W | 5.65 | 6.01 | 5.65 | 5.33 | 5 | 4.49 | 4.5 | 4.59 | 4.67 | 5.25 | 5.7 | 5.55 | 5.2 |
| Africa | EG | Cairo | 29 35' N | 31 09' E | 3.39 | 4.17 | 5.24 | 6.49 | 7.11 | 8 | 7.88 | 7.4 | 6.42 | 5.07 | 3.86 | 3.19 | 5.68 |
| Africa | DZ | alger | 36 50' N | 3 E | 2.22 | 2.94 | 3.87 | 5 | 5.88 | 6.69 | 7.23 | 6.48 | 5.15 | 3.53 | 2.43 | 2.02 | 4.45 |
| Africa | CM | Yaounde | 3 48' N | 11 30' W | 4.94 | 5.38 | 5.16 | 4.68 | 4.46 | 4.42 | 5.17 | 5.07 | 5.03 | 5.4 | 5.29 | 4.83 | 4.98 |
| Africa | DJ | djibouti | 11 33' N | 43 09' E | 5.6 | 5.77 | 6.59 | 6.81 | 6.85 | 6.87 | 6.46 | 6.47 | 6.56 | 6.77 | 6.22 | 5.55 | 6.37 |
| Africa | CF | Bangui | 18 32' N | 120 36' E | 4.13 | 4.97 | 5.99 | 6.61 | 6.17 | 5.53 | 5.73 | 4.87 | 5.07 | 4.55 | 4.07 | 3.81 | 5.12 |
| Asia Pacific | YE | Aden | 12 50' N | 45 02' E | 5.45 | 5.78 | 6.52 | 6.48 | 6.71 | 6.72 | 6.33 | 6.33 | 6.41 | 6.54 | 5.99 | 5.39 | 6.22 |
| Asia Pacific | VN | Hanoi | 21 N | 105 54' E | 2.52 | 2.94 | 3.81 | 4.34 | 4.66 | 4.51 | 4.62 | 4.62 | 4.57 | 3.64 | 3.29 | 3.17 | 3.89 |
| Asia Pacific | TR | Ankara | 39 57' N | 32 53' E | 1.77 | 2.38 | 3.69 | 4.54 | 5.53 | 6.63 | 6.99 | 6.55 | 5.22 | 3.24 | 1.99 | 1.51 | 4.17 |
| Asia Pacific | TH | Chiang Mai | 18 N | 99 E | 4.79 | 5.51 | 6.11 | 6.29 | 5.53 | 4.44 | 4.16 | 4.18 | 4.5 | 4.34 | 4.28 | 4.48 | 4.88 |
| Asia Pacific | TH | Bang Kok | 13 45' N | 100 30' E | 4.42 | 4.65 | 4.84 | 5.03 | 4.75 | 3.77 | 4.22 | 3.46 | 3.63 | 3.89 | 4.16 | 4.4 | 4.27 |
| Asia Pacific | SG | Singapore City | 1 N | 103 E | 4.43 | 5.52 | 5.05 | 5.05 | 4.62 | 4.66 | 4.51 | 4.61 | 4.49 | 4.5 | 3.98 | 3.93 | 4.61 |
| Asia Pacific | SA | Riyadh | 24 39' N | 46 42' E | 4.03 | 4.92 | 5.56 | 6.24 | 7.27 | 7.99 | 7.86 | 7.46 | 6.83 | 5.8 | 4.58 | 3.82 | 6.03 |
| Asia Pacific | PH | Manila | 14 37' N | 120 58' E | 4.82 | 5.62 | 6.42 | 6.75 | 6.19 | 4.96 | 4.94 | 4.41 | 4.86 | 4.63 | 4.59 | 4.5 | 5.22 |
| Asia Pacific | PH | Cebu | 10 19' N | 123 54' E | 4.53 | 5.15 | 5.83 | 6.25 | 5.9 | 4.83 | 4.76 | 4.93 | 4.96 | 4.75 | 4.49 | 4.44 | 5.07 |
| Asia Pacific | OM | Mascat | 23 37' N | 58 37' E | 4.34 | 5 | 5.85 | 6.69 | 7.54 | 7.56 | 6.91 | 6.71 | 6.55 | 5.93 | 4.95 | 4.23 | 6.29 |
| Asia Pacific | NZ | Wellington | 41 17' S | 174 47' E | 6.27 | 5.31 | 4.17 | 3 | 1.95 | 1.54 | 1.74 | 2.46 | 3.66 | 4.7 | 5.73 | 6.01 | 3.88 |
| Asia Pacific | NZ | Christchurch | 43 32s | 172 37e | 5.9 | 4.95 | 3.86 | 2.75 | 1.72 | 1.31 | 1.47 | 2.15 | 3.3 | 4.34 | 5.43 | 5.64 | 3.57 |
| Asia Pacific | NZ | Auckland | 36 52' S | 174 45' E | 6.37 | 5.9 | 4.71 | 3.43 | 2.44 | 2 | 2.25 | 2.95 | 4.13 | 5.23 | 6.05 | 6.56 | 4.34 |
| Asia Pacific | MY | Kuala Lumpur | 3 07' N | 101 42' E | 4.54 | 5.27 | 5.14 | 5.05 | 4.8 | 4.98 | 4.91 | 4.78 | 4.54 | 4.51 | 4.23 | 4.07 | 4.7 |
| Asia Pacific | MN | Ulaanbaatar | 47 55' N | 106 54' E | 1.79 | 2.77 | 4.24 | 5.53 | 6.26 | 6.15 | 5.55 | 4.88 | 4.17 | 3 | 1.82 | 1.4 | 4.3 |
| Asia Pacific | MM | Yangon | 16 47' N | 96 09' E | 5.4 | 6.06 | 6.65 | 6.69 | 5.14 | 3.24 | 3.3 | 2.99 | 4.12 | 4.51 | 4.82 | 5.05 | 4.65 |
| Asia Pacific | LB | Beirut | 33 54N | 35 28E | 2.64 | 3.4 | 4.63 | 6.03 | 6.96 | 7.9 | 7.84 | 7.19 | 6.13 | 4.5 | 3.14 | 2.44 | 5.68 |
| Asia Pacific | LA | Vientiane | 18 07' N | 102 35' E | 4.3 | 4.94 | 5.52 | 5.74 | 5.11 | 4.24 | 4.22 | 4.19 | 4.61 | 4.26 | 4.21 | 4.24 | 4.63 |
| Asia Pacific | KR | Seoul | 37 31' N | 127 E | 2.62 | 3.4 | 4.29 | 5.24 | 5.63 | 5.15 | 4.26 | 4.55 | 3.99 | 3.64 | 2.6 | 2.24 | 4.16 |
| Asia Pacific | KP | P' yongyang | 39 N | 125 18' E | 2.5 | 3.35 | 4.5 | 5.17 | 5.6 | 5.35 | 4.51 | 4.63 | 4.22 | 3.51 | 2.46 | 2.09 | 4.2 |
| Asia Pacific | KH | Phnom penh | 11 33' N | 104 51' E | 5.27 | 5.78 | 6.02 | 5.76 | 5.09 | 4.3 | 4.55 | 4.07 | 4.34 | 4.41 | 4.88 | 5.03 | 4.85 |
| Asia Pacific | JP | Tokyo | 35 45' N | 139 38' E | 2.31 | 2.99 | 3.7 | 4.9 | 5.07 | 4.47 | 4.88 | 5.42 | 3.82 | 2.98 | 2.5 | 2.23 | 4 |
| Asia Pacific | JO | Amman | 31 57' N | 35 57' E | 2.93 | 3.67 | 4.83 | 6.04 | 6.88 | 7.91 | 7.86 | 7.27 | 6.25 | 4.71 | 3.47 | 2.76 | 5.8 |
| Asia Pacific | IQ | Baghdad | 33 20' N | 44 24' E | 2.79 | 3.64 | 4.59 | 5.76 | 6.83 | 8.1 | 7.97 | 7.29 | 6.25 | 4.44 | 3.04 | 2.52 | 5.27 |
| Asia Pacific | IN | Bangalore | 12 57' N | 77 37' E | 5 | 5.9 | 6.44 | 6.42 | 6.13 | 4.76 | 4.48 | 4.59 | 4.98 | 4.68 | 4.34 | 4.4 | 5.18 |
| Asia Pacific | IN | Bombay | 18 33' N | 72 32' E | 5.22 | 6.03 | 6.66 | 7.05 | 6.77 | 4.59 | 3.54 | 3.4 | 4.72 | 5.39 | 5.15 | 4.8 | 5.28 |
| Asia Pacific | IN | New Delhi | 28 N | 77 E | 3.68 | 4.47 | 5.5 | 6.6 | 7.08 | 6.55 | 5.01 | 4.62 | 5.11 | 4.99 | 4.15 | 3.42 | 5.1 |
| Asia Pacific | IR | Bandar' Abbas | 27 15' N | 56 15' E | 3.63 | 4.43 | 5.14 | 6.29 | 7.43 | 7.96 | 7.41 | 6.97 | 6.58 | 5.51 | 4.29 | 3.37 | 5.75 |
| Asia Pacific | IR | Mashhad | 36 16' N | 59 34' E | 2.22 | 2.97 | 3.88 | 5.21 | 6.29 | 7.49 | 7.41 | 6.78 | 5.7 | 4.13 | 2.78 | 2.06 | 4.74 |
| Asia Pacific | IR | Tehran | 35 40' N | 51 26' E | 2.23 | 2.84 | 3.72 | 5.12 | 5.99 | 7.32 | 7.2 | 6.41 | 5.59 | 3.9 | 2.61 | 2.02 | 4.58 |
| Asia Pacific | IR | Tabriz | 38 48' N | 46 18' E | 1.79 | 2.4 | 3.37 | 4.58 | 5.54 | 6.71 | 6.97 | 6.06 | 5.2 | 3.26 | 2.14 | 1.56 | 4.13 |
| Asia Pacific | IL | Tel Aviv | 32 05' N | 34 46' E | 2.78 | 3.5 | 4.73 | 6.03 | 6.86 | 7.87 | 7.81 | 7.22 | 6.19 | 4.63 | 3.32 | 2.62 | 5.73 |
| Asia Pacific | ID | Jakarta | 6 11' S | 106 50' E | 4.15 | 4.59 | 5 | 4.94 | 4.88 | 4.71 | 5.09 | 5.46 | 5.66 | 5.36 | 4.76 | 4.47 | 5.03 |
| Asia Pacific | AU | Melbourne | 37 47' S | 144 58' E | 6.78 | 6.22 | 4.76 | 3.4 | 2.29 | 1.84 | 2.04 | 2.79 | 3.94 | 5.27 | 6.28 | 6.46 | 4.34 |
| Asia Pacific | AU | Perth | 31 57' S | 115 52' E | 7.7 | 6.75 | 5.41 | 4.16 | 3.06 | 2.67 | 2.89 | 3.66 | 4.76 | 6.09 | 7.04 | 7.76 | 5.16 |
| Asia Pacific | AU | Sydney | 34 S | 151 0' E | 6.34 | 5.68 | 4.87 | 3.6 | 2.74 | 2.5 | 2.67 | 3.53 | 4.67 | 5.61 | 6.32 | 6.6 | 4.59 |
| Asia Pacific | BD | Dhaka | 23 42' N | 90 22' E | 4.44 | 5.08 | 5.87 | 6.06 | 5.5 | 4.41 | 4.09 | 4.37 | 4.17 | 4.5 | 4.37 | 4.13 | 4.75 |
| Asia Pacific | CN | Beijing | 39 55' N | 116 25' E | 2.37 | 2.92 | 3.58 | 5.61 | 4.83 | 5.68 | 5.42 | 4.49 | 4.25 | 3.2 | 2.66 | 2.04 | 3.92 |
| Asia Pacific | CN | Nanjing | 32 03' N | 118 53' E | 2.04 | 2.22 | 2.65 | 4.5 | 3.84 | 4.47 | 4.93 | 4.5 | 3.67 | 3.02 | 2.88 | 2.08 | 3.4 |
| Asia Pacific | CN | Shanghai | 31 10' N | 121 28' E | 2.29 | 2.63 | 3.07 | 4.54 | 4.38 | 4.59 | 5.52 | 5.23 | 4.03 | 3.39 | 2.97 | 2.38 | 4.01 |
| Asia Pacific | CN | Hongkong | 22 18' N | 114 10' E | 2.59 | 2.56 | 3.06 | 3.93 | 4.13 | 4.74 | 5.81 | 4.95 | 4.68 | 4.05 | 3.56 | 2.93 | 4.18 |
| Asia Pacific | AU | Brisbane | 27 99' S | 153 8' E | 6.93 | 6.09 | 5.44 | 4.34 | 3.5 | 3.29 | 3.52 | 4.43 | 5.62 | 6.18 | 6.74 | 6.93 | 5.25 |
| Asia Pacific | AU | Hobart | 42 52' S | 147 19' E | 5.97 | 5.33 | 4.05 | 2.73 | 1.79 | 1.44 | 1.68 | 2.41 | 3.6 | 4.78 | 5.92 | 6.18 | 3.82 |
| Asia Pacific | AU | Adelaide | 34 55' S | 138 36' E | 7.2 | 6.58 | 5.18 | 3.85 | 2.65 | 2.23 | 2.48 | 3.2 | 4.46 | 5.69 | 6.59 | 6.74 | 4.74 |
| Asia Pacific | AE | Abu Dhabi | 24 28' N | 54 22' E | 3.92 | 4.5 | 5.22 | 5.87 | 7.06 | 7.33 | 6.9 | 6.64 | 6.39 | 5.53 | 4.54 | 3.79 | 5.64 |
| Canada | BF | Ouagadougou | 12 24' N | 1 30' E | 5.48 | 6.43 | 6.56 | 6.62 | 6.53 | 6.16 | 5.76 | 5.48 | 5.87 | 6.18 | 5.83 | 5.35 | 6.02 |
| Canada | QC | Montreal | 45 ? 28' N | 73 ? 45' W | 1.45 | 2.36 | 3.41 | 4.25 | 4.91 | 5.42 | 5.55 | 4.76 | 3.52 | 2.18 | 1.43 | 1.21 | 3.37 |
| Canada | SK | Regina | 45 ? 19' N | 65 ? 53' W | 1.14 | 1.96 | 3.02 | 4.69 | 5.48 | 5.79 | 6.14 | 4.96 | 3.42 | 2.29 | 1.3 | 0.95 | 3.42 |
| Canada | ON | Toronto | 43 ? 41' N | 79 ? 38' W | 1.44 | 2.27 | 3.19 | 4.13 | 5.15 | 5.83 | 5.67 | 4.82 | 3.66 | 2.47 | 1.48 | 1.2 | 3.44 |
| Canada | NL | St. Johns | 45 ? 19' N | 65 ? 53' W | 1.56 | 2.27 | 3.48 | 4.19 | 4.76 | 5.05 | 5.05 | 4.54 | 3.53 | 2.29 | 1.43 | 1.27 | 3.28 |
| Canada | NS | Halifax | 44 ? 39' N | 63 ? 34' W | 1.56 | 2.31 | 3.46 | 4.09 | 4.82 | 5.27 | 5.41 | 4.86 | 3.92 | 2.54 | 1.53 | 1.3 | 3.42 |
| Canada | MB | Winnipeg | 49 ? 54' N | 97 ? 14' W | 1.21 | 2.08 | 3.27 | 4.55 | 5.54 | 5.8 | 5 | 4.84 | 3.32 | 2.21 | 1.33 | 1.02 | 3.41 |
| Canada | AB | Edmonton | 53 ? 34' N | 113 ? 31' W | 1.45 | 2.36 | 3.41 | 4.25 | 4.91 | 5.42 | 5.55 | 4.76 | 3.52 | 2.18 | 1.43 | 1.21 | 3.37 |
| Canada | BC | Victoria | 48 ? 25' N | 123 ? 19' W | 1 | 1.82 | 2.93 | 4.01 | 5.13 | 5.54 | 5.85 | 5.28 | 3.88 | 2.17 | 1.11 | 0.86 | 3.29 |
| Europe | HU | Budapest | 47 30' N | 19 3' E | 1 | 1.71 | 2.76 | 3.9 | 5.03 | 5.3 | 5.62 | 4.84 | 3.57 | 2.24 | 1.17 | 0.88 | 3.17 |
| Europe | GR | Athens | 38 N | 23 43' E | 2 | 2.52 | 3.67 | 5.21 | 6.38 | 7.52 | 7.61 | 6.91 | 5.57 | 3.5 | 2.16 | 1.63 | 4.56 |
| Europe | FX | Toulouse | 43 37' N | 1 26' E | 1.39 | 2.14 | 3.19 | 4.03 | 4.82 | 5.16 | 5.86 | 5.07 | 4.09 | 2.48 | 1.58 | 1.25 | 3.75 |
| Europe | FX | Paris | 48 52' N | 2 20' E | 0.89 | 1.62 | 2.62 | 3.95 | 4.9 | 4.83 | 5.35 | 4.61 | 3.33 | 2 | 1.12 | 0.72 | 3.34 |
| Europe | FX | Lyon | 45 46' N | 4 50' E | 1.26 | 1.97 | 3.02 | 4.08 | 4.97 | 5.4 | 6.03 | 5.23 | 3.93 | 2.27 | 1.43 | 1.08 | 3.74 |
| Europe | ES | Alicante | 38 40' N | 0 30' W | 2.23 | 3.02 | 4.26 | 5.39 | 6.13 | 6.89 | 7.34 | 6.53 | 5.11 | 3.45 | 2.34 | 1.94 | 4.94 |
| Europe | ES | Barcelona | 41 24' N | 2 9' E | 1.89 | 2.71 | 3.97 | 4.99 | 5.82 | 6.56 | 7.01 | 6.07 | 4.72 | 3.11 | 2.04 | 1.7 | 4.6 |
| Europe | ES | Malaga | 36 42' N | 4 42' W | 2.52 | 3.24 | 4.51 | 5.4 | 6.35 | 7.09 | 7.64 | 6.81 | 5.39 | 3.7 | 2.58 | 2.14 | 5.16 |
| Europe | ES | Madrid | 40 25' N | 3 41' W | 1.93 | 2.75 | 4.09 | 4.83 | 5.85 | 6.52 | 7.11 | 6.3 | 4.91 | 3.07 | 1.97 | 1.59 | 4.62 |
| Europe | DE | Munich | 48 05' N | 11 23' E | 1.05 | 1.8 | 2.82 | 3.95 | 4.84 | 4.65 | 5.14 | 4.46 | 3.2 | 2 | 1.02 | 0.79 | 2.98 |
| Europe | DE | Hamburg | 53 33' N | 9 59' E | 0.54 | 1.11 | 2.09 | 3.68 | 4.86 | 4.47 | 4.47 | 3.89 | 2.59 | 1.48 | 0.69 | 0.4 | 2.52 |
| Europe | CR | Zagreb | 45 29' N | 15 35' E | 1.3 | 2 | 2.94 | 3.91 | 5.03 | 5.37 | 5.93 | 5.19 | 3.94 | 2.39 | 1.39 | 1.09 | 3.72 |
| Europe | CY | Limassol | 34 40' N | 33 03' E | 2.52 | 3.26 | 4.54 | 6 | 6.85 | 7.81 | 7.8 | 7.18 | 6.11 | 4.43 | 3.02 | 2.31 | 5.61 |
| Europe | BG | Sofija | 42 40' N | 23 18' E | 1.5 | 2.04 | 2.97 | 4.05 | 5 | 5.8 | 6.29 | 5.68 | 4.46 | 2.75 | 1.62 | 1.27 | 3.99 |
| Europe | BE | Bruxelles | 50 45' N | 4 30' E | 0.74 | 1.31 | 2.29 | 3.68 | 4.67 | 4.48 | 4.82 | 4.2 | 2.86 | 1.73 | 0.92 | 0.56 | 3.02 |
| Europe | AT | Vienna | 48 13' N | 16 22' E | 1.1 | 1.81 | 2.8 | 3.76 | 4.76 | 5.12 | 5.72 | 4.98 | 3.68 | 2.15 | 1.28 | 0.93 | 3.52 |
| Europe | YU | Beograd | 44 50' N | 20 30' E | 1.29 | 1.89 | 2.92 | 3.86 | 4.88 | 5.45 | 6 | 5.3 | 4.05 | 2.5 | 1.4 | 1.11 | 3.39 |
| Europe | SZ | Lausanne | 46 32' N | 6 39' E | 1.1 | 1.81 | 2.8 | 3.76 | 4.76 | 5.12 | 5.72 | 4.98 | 3.68 | 2.15 | 1.28 | 0.93 | 3.17 |
| Europe | SZ | Bern | 46 57' N | 7 26' E | 1.1 | 1.77 | 2.74 | 3.6 | 4.7 | 5.07 | 5.68 | 4.95 | 3.66 | 2.18 | 1.26 | 0.92 | 3.14 |
| Europe | UK | London | 51 32' N | 0 5' W | 0.67 | 1.26 | 2.22 | 3.48 | 4.54 | 4.51 | 4.74 | 4.01 | 2.86 | 1.65 | 0.89 | 0.52 | 2.61 |
| Europe | UK | Edinburgh | 55 55' N | 3' 10' W | 0.44 | 0.94 | 1.86 | 3.18 | 4.33 | 4.34 | 4.13 | 3.41 | 2.43 | 1.2 | 0.59 | 0.32 | 2.26 |
| Europe | UA | Odessa | 46 30' N | 30 46' E | 1.08 | 1.78 | 2.68 | 3.87 | 5.4 | 5.7 | 6.39 | 5.63 | 3.96 | 2.45 | 1.06 | 0.87 | 3.41 |
| Europe | PT | Oviedo | 43 21' N | 5 50' W | 1.67 | 2.29 | 3.44 | 4.59 | 5.56 | 6.32 | 6.86 | 5.95 | 4.51 | 2.71 | 1.77 | 1.46 | 3.93 |
| Europe | PT | Lisboa | 38 42' N | 9 11' W | 2.27 | 2.99 | 4.3 | 5.15 | 6.13 | 6.46 | 6.89 | 6.33 | 5.11 | 3.44 | 2.27 | 1.84 | 4.43 |
| Europe | RO | Bucharest | 44 26' N | 26 06' E | 1.36 | 1.94 | 2.91 | 3.94 | 5.03 | 5.6 | 6.15 | 5.53 | 4.15 | 2.59 | 1.37 | 1.1 | 3.47 |
| Europe | NO | Oslo | 59 56' N | 10 44' E | 0.3 | 0.87 | 1.68 | 3.12 | 4.65 | 4.84 | 4.59 | 3.36 | 2.22 | 1.02 | 0.42 | 0.19 | 2.27 |
| Europe | NL | Amsterdam | 52 21' N | 4 54' E | 0.61 | 1.21 | 2.27 | 3.76 | 4.88 | 4.73 | 4.78 | 4.13 | 2.8 | 1.6 | 0.78 | 0.45 | 2.67 |
| Europe | IT | Rome | 41 53' N | 12 30' E | 1.78 | 2.52 | 3.71 | 4.87 | 5.98 | 6.84 | 7.08 | 6.34 | 4.83 | 3.08 | 1.98 | 1.56 | 4.21 |
| Europe | IT | Milan | 45 28' N | 9 12' E | 1.27 | 1.89 | 2.91 | 3.65 | 4.84 | 5.36 | 5.97 | 5.21 | 3.91 | 2.4 | 1.42 | 1.08 | 3.33 |
| Europe | IE | Dublin | 53 20' N | 6 15' W | 0.56 | 1.07 | 1.97 | 3.32 | 4.4 | 4.3 | 4.3 | 3.4 | 2.69 | 1.43 | 0.77 | 0.43 | 2.39 |
| South America | Brazil | Fortaleza | 03? 43' S | 38? 31' W | 5.85 | 5.44 | 4.82 | 4.8 | 5.11 | 5.34 | 5.74 | 6.34 | 6.6 | 6.62 | 6.5 | 6.16 | 5.78 |
| South America | Brazil | Curitiba | 25? 26' S | 49? 15' W | 5.48 | 4.88 | 4.32 | 3.57 | 2.95 | 2.83 | 2.96 | 3.47 | 3.87 | 4.65 | 5.44 | 5.41 | 4.15 |
| South America | Brazil | Brasilia | 15? 52' S | 47? 56' W | 5.21 | 5.15 | 5.09 | 4.99 | 4.8 | 4.59 | 4.86 | 5.46 | 5.28 | 5.23 | 4.97 | 4.82 | 5.04 |
| South America | Brazil | Belo Horizonte | 19? 55' S | 43? 56' W | 5.45 | 5.63 | 5.34 | 4.78 | 4.3 | 4.09 | 4.32 | 4.82 | 5.05 | 5.26 | 5.25 | 4.98 | 4.94 |
| South America | Brazil | Belem | 01? 27' S | 48? 29' W | 4.54 | 4.34 | 4.26 | 4.46 | 4.75 | 4.99 | 5.27 | 5.5 | 5.85 | 5.79 | 5.52 | 4.96 | 5.02 |
| South America | Bolivia | Sucre | 19? 02' S | 65? 15' W | 1.67 | 2.29 | 3.47 | 4.58 | 5.59 | 6.37 | 6.86 | 5.97 | 4.51 | 2.73 | 1.77 | 1.46 | 3.94 |
| South America | Bolivia | Santa Cruz | 17? 47' S | 63? 10' W | 4.57 | 4.9 | 4.57 | 3.92 | 3.44 | 3.25 | 3.44 | 4.01 | 4.45 | 5 | 5.21 | 5.01 | 4.31 |
| South America | Bolivia | La Paz | 16? 29' S | 68? 08' W | 5.3 | 5.57 | 5.16 | 5.01 | 4.78 | 4.37 | 4.51 | 4.96 | 5.66 | 5.98 | 6.15 | 5.92 | 5.28 |
| South America | Argentina | Rio Gallegos | 51? 37' S | 69? 13' W | 5.47 | 4.63 | 3.32 | 2.02 | 1.07 | 0.71 | 0.81 | 1.61 | 2.87 | 4.26 | 5.53 | 5.79 | 3.17 |
| South America | Argentina | Cordoba | 31? 24' S | 64? 12' W | 7.07 | 6.3 | 4.9 | 3.87 | 3.01 | 2.65 | 2.79 | 3.63 | 4.76 | 5.93 | 6.63 | 6.96 | 4.88 |
| South America | Argentina | Buenos Aires | 34? 36' S | 58? 23' W | 6.44 | 5.67 | 4.53 | 3.53 | 2.74 | 2.04 | 2.31 | 3.27 | 4.23 | 5.12 | 6.36 | 6.44 | 4.39 |
| South America | Dominican Rep. | Santiago | 18? 29' N | 69? 54' W | 3.89 | 4.46 | 5.24 | 5.53 | 5.52 | 5.48 | 5.41 | 5.13 | 4.8 | 4.46 | 4.03 | 3.78 | 4.81 |
| South America | Martinique | Fort de France | 14? 37' N | 61? 05' W | 5.35 | 5.98 | 6.59 | 6.94 | 6.7 | 6.42 | 6.49 | 6.45 | 6.03 | 5.87 | 5.15 | 5.15 | 6.09 |
| South America | Puerto Rico | San Juan | 18? 15' N | 66? 30' W | 4.26 | 4.9 | 5.7 | 6.09 | 5.89 | 6.09 | 6.08 | 5.78 | 5.26 | 4.8 | 4.36 | 4.15 | 5.28 |
| South America | Jamaica | Kingston | 17? 58' N | 76? 48' W | 4.92 | 5.67 | 6.45 | 6.8 | 6.5 | 6.82 | 6.84 | 6.61 | 6.23 | 5.45 | 4.76 | 4.58 | 5.97 |
| South America | Cuba | Havana | 23? 09' N | 82? 21' W | 4.09 | 4.97 | 5.92 | 7.06 | 7.15 | 7.1 | 6.9 | 6.86 | 6.1 | 5.12 | 4.26 | 3.74 | 5.77 |
| South America | Panama | Panama City | 08? 58' N | 79? 33' W | 5.27 | 5.92 | 6.23 | 5.75 | 4.78 | 4.11 | 4.16 | 4.15 | 4.24 | 3.99 | 4.23 | 4.66 | 4.79 |
| South America | Nicaragua | Managua | 12? 10' N | 86? 15' W | 5.34 | 5.89 | 6.59 | 6.54 | 5.83 | 5.67 | 5.7 | 5.69 | 5.43 | 5.39 | 5.15 | 5.05 | 5.69 |
| South America | Mexico | Veracruz | 19? 10' N | 96? 07' W | 3.55 | 4.13 | 4.86 | 5.35 | 5.4 | 5.12 | 5.15 | 5.17 | 4.66 | 4.45 | 3.92 | 3.43 | 4.6 |
| South America | Mexico | Tijuana | 32? 32' N | 117? 01' W | 3.32 | 4.15 | 5.23 | 6.37 | 6.61 | 6.43 | 6.46 | 6.31 | 5.4 | 4.26 | 3.65 | 3.08 | 5.11 |
| South America | Mexico | Puerto Vallarta | 20? 39' N | 105? 14' W | 4.2 | 5.29 | 6.39 | 7.12 | 7.51 | 6.96 | 6.17 | 5.99 | 5.32 | 5.3 | 4.82 | 4 | 5.76 |
| South America | Mexico | Oaxaca | 17? 04' N | 96? 43' W | 4.36 | 4.99 | 5.74 | 6.08 | 5.86 | 5.01 | 4.92 | 4.95 | 4.43 | 4.63 | 4.38 | 4.08 | 4.95 |
| South America | Mexico | Monterrey | 25? 40' N | 100? 23' W | 3.33 | 4.2 | 5.4 | 5.71 | 6.06 | 5.89 | 5.59 | 5.44 | 4.76 | 4.49 | 3.9 | 3.23 | 4.83 |
| South America | Mexico | Mexico City | 19? 26' N | 99? 08' W | 4.34 | 5.07 | 5.89 | 5.95 | 5.9 | 5.03 | 4.76 | 4.86 | 4.57 | 4.73 | 4.57 | 4.29 | 5 |
| South America | Mexico | La Paz | 24? 09' N | 110? 18' W | 3.73 | 4.67 | 5.75 | 6.63 | 7.16 | 7.07 | 6.4 | 6.06 | 5.52 | 4.93 | 4.11 | 3.51 | 5.46 |
| South America | Mexico | Guadalajara | 20? 40' N | 103? 40' W | 4.24 | 5.18 | 6.21 | 6.71 | 6.89 | 6 | 5.23 | 5.41 | 5.14 | 5.11 | 4.79 | 4.13 | 5.42 |
| South America | Mexico | Chihuahua | 28? 39' N | 106? 05' W | 3.41 | 4.34 | 5.63 | 6.43 | 6.88 | 6.53 | 5.69 | 5.3 | 5.14 | 4.65 | 3.89 | 3.26 | 5.1 |
| South America | Mexico | Cancun | 21? 10' N | 86? 50' W | 4.16 | 5.14 | 6.04 | 6.86 | 6.79 | 6.47 | 6.63 | 6.65 | 5.86 | 5.19 | 4.51 | 3.9 | 5.68 |
| South America | Mexico | Acapulco | 16? 50' N | 99? 54' W | 5.46 | 6.3 | 7.17 | 7.41 | 7.06 | 6.16 | 6.29 | 6.2 | 5.45 | 5.94 | 5.56 | 5.19 | 6.18 |
| South America | Honduras | Tegucigalpa | 14? 05' N | 87? 14' W | 4.26 | 5.08 | 5.84 | 5.99 | 5.54 | 5.35 | 5.34 | 5.47 | 5.04 | 4.43 | 4.15 | 3.91 | 5.03 |
| South America | Guatemala | Guatemala City | 14? 37' N | 90? 31' W | 4.93 | 5.48 | 5.9 | 5.81 | 5.35 | 4.91 | 5.27 | 5.12 | 4.59 | 4.68 | 4.65 | 4.62 | 5.11 |
| South America | El Salvador | San Salvador | 13? 40' N | 89? 10' W | 5.58 | 6.23 | 6.68 | 6.52 | 5.95 | 5.74 | 6.22 | 6.18 | 5.49 | 5.61 | 5.42 | 5.3 | 5.91 |
| South America | Costa Rica | San Jose | 09? 59' N | 84? 04' W | 6.09 | 6.74 | 7.23 | 6.64 | 5.26 | 5 | 4.94 | 4.84 | 4.76 | 4.63 | 4.63 | 5.3 | 5.51 |
| South America | Belize | Belize City | 17? 30' N | 88? 11' W | 3.73 | 4.59 | 5.45 | 5.97 | 5.75 | 5.19 | 5.03 | 5.16 | 4.82 | 4.5 | 3.99 | 3.54 | 4.81 |
| USA | IL | Chicago | 41 53' N | 87 38' W | 1.5 | 2.45 | 3.2 | 4.48 | 5.56 | 6.07 | 5.68 | 5.27 | 4.51 | 3.07 | 1.69 | 1.26 | 3.72 |
| USA | IN | Indianapolis | 39 44' N | 86 17' W | 1.67 | 2.59 | 3.28 | 4.67 | 5.46 | 6.11 | 5.79 | 5.37 | 4.76 | 3.33 | 1.97 | 1.46 | 3.87 |
| USA | ID | Boise | 43 34' N | 116 13' W | 1.73 | 2.72 | 3.77 | 5.22 | 5.9 | 6.57 | 7.17 | 6.12 | 5.28 | 3.29 | 1.74 | 1.46 | 4.24 |
| USA | IA | Dubuque | 42 24' N | 90 42' W | 1.64 | 2.58 | 3.34 | 4.57 | 5.54 | 6.06 | 5.81 | 5.26 | 4.33 | 3.03 | 1.72 | 1.35 | 3.77 |
| USA | HI | Honolulu | 21 20' N | 157 55' W | 4.38 | 5.15 | 5.99 | 6.69 | 7.05 | 7.48 | 7.37 | 7.07 | 6.51 | 5.46 | 4.41 | 4.01 | 5.96 |
| USA | GA | Atlanta | 33 39' N | 84 26' W | 2.31 | 3.37 | 4.08 | 5.2 | 6.02 | 6.01 | 5.81 | 5.59 | 4.76 | 3.95 | 2.98 | 2.33 | 4.37 |
| USA | FL | Miami | 25 48' N | 80 16' W | 3.72 | 4.61 | 5.42 | 6.4 | 6.61 | 6.29 | 6.26 | 6.08 | 5.47 | 4.84 | 3.96 | 3.46 | 5.26 |
| USA | DE | Dover | 39 8' N | 75 28' W | 1.85 | 2.62 | 3.6 | 4.33 | 5.44 | 5.91 | 5.64 | 5.3 | 4.38 | 3.23 | 2.21 | 1.66 | 3.84 |
| USA | CT | Hartford | 41 44' N | 72 39' W | 1.7 | 2.43 | 3.48 | 4.07 | 5.14 | 5.58 | 5.38 | 5.04 | 4.13 | 2.91 | 1.81 | 1.42 | 3.59 |
| USA | CO | Denver | 39 45' N | 104 52' W | 2.25 | 3.2 | 4.32 | 5.61 | 6.11 | 6.71 | 6.5 | 5.86 | 5.47 | 4.01 | 2.59 | 1.98 | 4.55 |
| USA | CA | San Francisco | 38 31' N | 121 30' W | 2.35 | 3.33 | 4.42 | 5.95 | 6.84 | 7.39 | 7.55 | 6.51 | 5.75 | 3.92 | 2.65 | 2.06 | 4.89 |
| USA | CA | Los Angeles | 34 N | 118 W | 3.09 | 4.25 | 5.09 | 6.58 | 7.29 | 7.62 | 7.45 | 6.72 | 6.11 | 4.42 | 3.43 | 2.72 | 5.4 |
| USA | AZ | Phoenix | 33 26' N | 112 1' W | 3.25 | 4.41 | 5.17 | 6.76 | 7.42 | 7.7 | 6.99 | 6.11 | 6.02 | 4.44 | 3.52 | 2.75 | 5.38 |
| USA | AR | little rock | 32 25' N | 94 44' W | 2.36 | 3.39 | 4.01 | 5.32 | 5.71 | 6.19 | 6.15 | 5.85 | 5.25 | 4.17 | 2.95 | 2.25 | 4.46 |
| USA | AK | Anchorage | 61 10' N | 150 1' W | 0.21 | 0.76 | 1.68 | 3.12 | 3.98 | 4.58 | 4.25 | 3.16 | 1.98 | 0.98 | 0.37 | 0.12 | 2.09 |
| USA | AL | Birming han | 33 34' N | 86 45' W | 2.29 | 3.31 | 4.04 | 5.14 | 5.92 | 5.98 | 5.81 | 5.7 | 4.8 | 3.93 | 2.96 | 2.25 | 4.34 |
| USA | KS | Kansas City | 39 12' N | 94 36' W | 2.06 | 2.89 | 3.62 | 4.92 | 5.58 | 6.17 | 6.21 | 5.59 | 4.9 | 3.49 | 2.2 | 1.75 | 4.11 |
| USA | KY | Louisville | 38 11' N | 85 44' W | 1.71 | 2.65 | 3.32 | 4.73 | 5.38 | 6.08 | 5.79 | 5.35 | 4.8 | 3.42 | 2.1 | 1.56 | 3.9 |
| USA | LA | New Orleans | 29 37' N | 90 5' W | 2.64 | 3.73 | 4.67 | 5.8 | 6.6 | 6.15 | 6.09 | 5.7 | 5.13 | 4.48 | 3.49 | 2.68 | 4.76 |
| USA | MA | Boston | 42 22' N | 71 2' W | 1.66 | 2.5 | 3.51 | 4.13 | 5.11 | 5.47 | 5.44 | 5.05 | 4.12 | 2.84 | 1.74 | 1.4 | 3.58 |
| USA | MD | Annapolis | 38 35' N | 76 21' W | 1.96 | 2.8 | 3.71 | 4.55 | 5.54 | 6.03 | 5.77 | 5.34 | 4.48 | 3.4 | 2.37 | 1.81 | 3.98 |
| USA | ME | Portland | 45 36' N | 122 36' W | 1.38 | 2.33 | 3.49 | 4.57 | 5.46 | 6.09 | 6.64 | 5.78 | 4.8 | 2.79 | 1.41 | 1.1 | 3.82 |
| USA | MI | Detroit | 42 25' N | 83 1' W | 1.43 | 2.33 | 3.19 | 4.34 | 5.44 | 5.98 | 5.64 | 4.99 | 4.25 | 2.73 | 1.52 | 1.14 | 3.58 |
| USA | MO | St.Louis | 38 45' N | 90 23' W | 2.02 | 2.82 | 3.52 | 4.97 | 5.56 | 6.21 | 6.05 | 5.63 | 4.91 | 3.55 | 2.21 | 1.73 | 4.09 |
| USA | MN | Minneapolis | 44 53' N | 93 13' W | 1.6 | 2.61 | 3.3 | 4.55 | 5.44 | 5.86 | 5.77 | 5.12 | 4.12 | 2.9 | 1.62 | 1.34 | 3.68 |
| USA | MS | Jackson | 42 16' N | 84 28' W | 1.47 | 2.41 | 3.22 | 4.33 | 5.46 | 5.93 | 5.57 | 4.99 | 4.3 | 2.78 | 1.55 | 1.17 | 3.59 |
| USA | MT | Billings | 45 48' N | 108 32' W | 1.55 | 2.57 | 3.52 | 4.82 | 5.63 | 6.45 | 6.39 | 5.75 | 4.67 | 3.19 | 1.77 | 1.3 | 3.96 |
| USA | MT | Great Falls | 43 33' N | 96 42' W | 1.3 | 2.36 | 3.41 | 4.84 | 5.56 | 6.18 | 6.44 | 5.53 | 4.4 | 2.9 | 1.53 | 1.11 | 3.79 |
| USA | NC | Charlotte | 35 13' N | 80 56' W | 2.22 | 3.17 | 3.95 | 4.98 | 5.8 | 6.01 | 5.76 | 5.27 | 4.58 | 3.75 | 2.76 | 2.21 | 4.2 |
| USA | ND | Fargo | 46 54' N | 96 48' W | 1.44 | 2.39 | 3.36 | 4.79 | 5.62 | 5.82 | 5.94 | 5.14 | 4.01 | 2.83 | 1.59 | 1.31 | 3.68 |
| USA | NE | Omaha | 41 18' N | 95 54' W | 1.92 | 2.76 | 3.45 | 4.74 | 5.6 | 6.14 | 6.11 | 5.46 | 4.74 | 3.34 | 2 | 1.57 | 3.98 |
| USA | NH | Manchester | 42 56' N | 71 26' W | 1.66 | 2.5 | 3.51 | 4.13 | 5.11 | 5.47 | 5.44 | 5.05 | 4.12 | 2.84 | 1.74 | 1.4 | 3.58 |
| USA | NJ | Trenton | 40 13' N | 74 46' W | 1.71 | 2.39 | 3.43 | 4.04 | 5.26 | 5.67 | 5.39 | 5.14 | 4.18 | 3 | 1.98 | 1.48 | 3.63 |
| USA | NM | Albuquerque | 35 3' N | 106 37' W | 2.92 | 3.97 | 4.92 | 6.3 | 6.68 | 6.94 | 6.66 | 5.8 | 5.68 | 4.18 | 3.16 | 2.5 | 4.97 |
| USA | NV | Las Vegas | 36 18' N | 115 16' W | 3.02 | 4.13 | 5.05 | 6.57 | 7.25 | 7.69 | 7.37 | 6.42 | 6.08 | 4.26 | 3.18 | 2.6 | 5.3 |
| USA | NY | New York | 41 N | 74 W | 1.67 | 2.37 | 3.41 | 3.93 | 5.11 | 5.48 | 5.26 | 5.01 | 4.05 | 2.85 | 1.82 | 1.4 | 3.53 |
| USA | OH | Columbus | 39 16' N | 85 54' W | 1.64 | 2.57 | 3.26 | 4.63 | 5.4 | 6.08 | 5.73 | 5.29 | 4.74 | 3.29 | 1.96 | 1.45 | 3.83 |
| USA | OK | Tulsa | 36 12' N | 95 54' W | 2.33 | 3.22 | 3.9 | 5.25 | 5.58 | 6.32 | 6.4 | 5.8 | 5.08 | 3.8 | 2.62 | 2.06 | 4.36 |
| USA | OR | Portland | 45 32' N | 122 40' W | 1.38 | 2.33 | 3.49 | 4.57 | 5.46 | 6.09 | 6.64 | 5.78 | 4.8 | 2.79 | 1.41 | 1.1 | 3.82 |
| USA | PA | Philadelphia | 39 53' N | 75 15' W | 1.85 | 2.62 | 3.6 | 4.33 | 5.44 | 5.91 | 5.64 | 5.3 | 4.38 | 3.23 | 2.21 | 1.66 | 3.84 |
| USA | PA | Pittsburgh | 40 27' N | 79 57' W | 1.59 | 2.4 | 3.26 | 4.07 | 5.05 | 5.53 | 5.27 | 4.94 | 4.05 | 2.88 | 1.86 | 1.41 | 3.53 |
| USA | RI | Providence | 41 44' N | 71 26' W | 1.7 | 2.46 | 3.53 | 4.2 | 5.17 | 5.67 | 5.48 | 5.08 | 4.21 | 2.97 | 1.8 | 1.43 | 3.64 |
| USA | SC | Columbia | 38 58' N | 92 22' W | 2.14 | 2.91 | 3.62 | 5.03 | 5.56 | 6.22 | 6.13 | 5.64 | 4.95 | 3.57 | 2.25 | 1.82 | 4.15 |
| USA | SD | Sioux Falls | 45 27' N | 98 25' W | 1.72 | 2.71 | 3.31 | 4.65 | 5.61 | 6.1 | 6.04 | 5.42 | 4.47 | 3.2 | 1.78 | 1.43 | 3.87 |
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Nasa Surface meteorology and Solar Energy Data Set
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