7.1 IBTrACS — Database Siklon Tropis Global
IBTrACS (International Best Track Archive for Climate Stewardship) adalah database resmi WMO yang mengkompilasi data jalur siklon tropis dari seluruh dunia sejak 1842. Data tersedia dalam format NetCDF dan CSV dari ncei.noaa.gov/products/international-best-track-archive.
% ── 7.1 Membaca IBTrACS ──────────────────────────────────
fname_tc = 'IBTrACS.WP.v04r00.nc'; % Wilayah Western Pacific
% Variabel utama
lon_tc = ncread(fname_tc, 'lon'); % [storm x time]
lat_tc = ncread(fname_tc, 'lat');
wind_tc = ncread(fname_tc, 'wmo_wind'); % Kecepatan angin maksimum (knot)
pres_tc = ncread(fname_tc, 'wmo_pres'); % Tekanan minimum (hPa)
year_tc = ncread(fname_tc, 'season'); % Tahun
name_tc = ncread(fname_tc, 'name'); % Nama siklon
fprintf('Jumlah total storm: %d\n', size(lon_tc, 1))
% ── 7.2 Plot Track Siklon ─────────────────────────────────
% Filter: hanya tahun 2000-2023, wilayah Indonesia (95-141E, 30S-20N)
years = squeeze(year_tc);
i_storms = find(years >= 2000 & years <= 2023);
figure('Position', [50 50 1200 700])
hold on
for i = i_storms'
lo = lon_tc(i, :);
la = lat_tc(i, :);
ws = wind_tc(i, :);
valid = ~isnan(lo) & ~isnan(la);
if sum(valid) < 2; continue; end
% Warna berdasarkan intensitas
max_ws = nanmax(ws);
if max_ws >= 130
clr = [0.6 0 0]; % Super typhoon: merah tua
elseif max_ws >= 96
clr = [0.9 0.2 0.2]; % Typhoon: merah
elseif max_ws >= 64
clr = [1 0.6 0]; % Severe TS: oranye
else
clr = [0.3 0.5 1]; % TS: biru
end
plot(lo(valid), la(valid), '-', 'Color', clr, 'LineWidth', 0.8)
end
load coastlines
plot(coastlon, coastlat, 'k', 'LineWidth', 0.5)
xlabel('Longitude'); ylabel('Latitude')
title('Track Siklon Tropis Western Pacific 2000-2023')
xlim([90 180]); ylim([-15 35])
grid on7.3 Density Map Siklon
% Density map menggunakan histogram 2D
res = 2; % Resolusi 2 derajat
lon_bins = 90:res:180;
lat_bins = -15:res:35;
density = zeros(length(lon_bins)-1, length(lat_bins)-1);
for i = i_storms'
lo = lon_tc(i, :);
la = lat_tc(i, :);
valid = ~isnan(lo) & ~isnan(la);
for t = find(valid)
[~, il] = histc(lo(t), lon_bins);
[~, ila] = histc(la(t), lat_bins);
if il > 0 && ila > 0
density(il, ila) = density(il, ila) + 1;
end
end
end
% Normalisasi ke track density per tahun per degree^2
density_norm = density / (2023-2000+1) / res^2;
figure
imagescn(lon_bins(1:end-1)+res/2, lat_bins(1:end-1)+res/2, density_norm')
cmocean('matter')
colorbar('Label', 'Track density (per tahun per deg^2)')
title('Track Density Siklon Tropis (2000-2023)')_(cropped).jpg)
