Global warming which leads to climate change has potential affect to Indonesia agriculture activities and production. Analyzing rainfall pattern and distribution is important to investigate the impact of global climate change to local climate. This study using rainfall data from 1976-2010 from both lowland and upland area of Lampung Province. The results show that rainfall tends to decrease since the 1990s which related to the years with El Nino event. Monsoonal pattern-having rain and dry season-still excist in Lampung; however, since most rain fell below the average, it could not meet crops water need. Farmers conclude that dry seasons were longer and seasonal pattern has been changed. Global climate change might affect Lampung rainfall distribution through changes on sea surface temperature which could intensify the El Nino effect. Therefore, watching the El Nino phenomena and how global warming affects it, is important in predicting local climate especially the rainfall distribution in order to prevent significant loss in agriculture productivities. ABSTRAKPemanasan global yang menyebabkan perubahan iklim memiliki potensi untuk mempengaruhi kegiatan dan produksi pertanian Indonesia. Kajian pola curah hujan dan distribusi sangat penting untuk mengetahui dampak perubahan iklim global terhadap iklim setempat. Penelitian ini menggunakan data curah hujan dari 1976-2010 dari kedua dataran rendah dan dataran tinggi wilayah Provinsi Lampung. Hasil penelitian menunjukkan bahwa curah hujan cenderung menurun sejak tahun 1990-an yang berhubungan dengan El Nino. Pola hujan musiman, musim hujan dan musing kering masih terjadi di Lampung; Namun, karena sebagian besar hujan jatuh di bawah rata-rata menyebabkan tidak bisa memenuhi kebutuhan air untuk pertanian. Petani menyimpulkan bahwa musim kemarau lebih panjang dan pola musiman telah berubah. Perubahan iklim global dapat mempengaruhi distribusi curah hujan Lampung melalui perubahan suhu permukaan laut yang dapat meningkatkan efek El Nino. Oleh karena itu, memperhatikan fenomena El Nino dan bagaimana pemanasan global mempengaruhi itu, penting dalam memprediksi iklim setempat terutama distribusi curah hujan untuk mencegah kerugian yang signifikan dalam produktivitas pertanian.Kata kunci: pemanasan global, perubahan iklim, distribusi curah hujan, El Nino

This work was carried out in collaboration between both authors. Author TKM designed the study, coordinated data collection for Bandar Lampung area, performed the statistical analysis and wrote the first draft of the manuscript. Author SS coordinated data and map collection for Jakarta area and managed the literature searches. Both authors read and approved the final manuscript.

Evapotranspiration is an important factor in estimating crops water use and then irigation schedule. Direct measurement of evapotranspiration is difficult since it is influenced by many factors. Estimation methods are developed for estimating evapotranspiration rate from meteorological data. One method which is recommended by FAO is Penman-Monteith Method (P-M). To evaluate whether this method could be accurately used in Lampung a comparison had been conducted with evaporation measurement on two climate stations in Lampung, Branti and Masgar with data set from 2006-2008. The result for Branti showed that observation data was lower than P-M for ET > 4 mm and higher for ET < 4; while for Masgar evaporation observation always higher than P-M. In general P-M was 1.09 times higher than observation in Branti and 0.89 lower in Masgar. Correlation coefficients between P-M and observation were low (r = 0.3 for Branti and r = 0.5 for Masgar). Two possible reasons for the disagrrement were first, there was an error in measuring water level on the evaporation pan, this showed by the fact that observed evaporation has low coefficient correlation with all meteorological data which have direct impact on evaporation (air temperature and humidity, wind speed and radiation); second, CROPWAT converted shunshine duration to be the radiation intensity with linear approach while field data showed that sunshine duration did not relate linearly with radiation intensity.

Irigasi pada tanaman nanas sangat penting karena mempengaruhi pertumbuhan dan produksi namun biayanya sangat mahal. Penelitian ini bertujuan untuk mengetahui pengaruh irigasi dan mulsa organik pada kadar air tanah dan pertumbuhan nanas. Penelitian ini dilakukan menggunakan perlakuan faktorial (5 x 2) dalam rancangan acak kelompok dengan tiga ulangan. Faktor pertama adalah panjang waktu irigasi (I), yang terdiri dari 5 waktu yaitu tanpa irigasi (I0), irigasi 1 bulan (I1), irigasi 2 bulan (I2), irigasi 3 bulan (I3), dan irigasi 4 bulan (I4). Faktor kedua adalah dosis kulit singkong (mulsa organik) terdiri dari 2 level 0 ton/ha (M0) dan 50 ton/ha (M1). Kadar air tanah diukur menggunakan Diviner 2000. Data kadar air tanah dianalisis dengan time series. Pertumbuhan tanaman dianalisis keragamannya dan diuji BNT pada taraf 5 %. Hasil penelitian menunjukkan kulit singkong 50 ton/ha pada umumnya hanya bertahan 2,5 bulan untuk mempertahankan kadar air. Mulsa kulit singkong lebih berperan ketika tanah mulai mengering. Pemberian mulsa kulit singkong berpengaruh terhadap tinggi dan berat basah tanaman sedangkan perlakuan, irigasi secara terpisah hanya berpengaruh terhadap berat basah tanaman. Interaksi antara irigasi dan kulit singkong berpengaruh terhadap berat basah tanaman. Meskipun kadar air tanah tersedia cukup saat memasuki musim hujan, namun tidak efektif dalam memulihkan keragaan tanaman nanas. Pemulihan terjadi setelah memasuk musim hujan dimana kadar air tanah tinggi.

Climate change has been understood from air temperature that constantly rising.  Therefore, to study the impact of climate change on crops growth and production should begin with study the impact of air temperature on crops, so that the technique of making crops adapt to the climate change could be developed.  Crops reaction on temperature change could be detected from the phenology and quantified with the Growing degree days (GDD). The objective of this research was to identify the impact of temperature change on strawberry phenology and production through cultivating on low land area and calculating the GDD at the end of the planting period.  The results showed that Strawberry on low land experienced some difficulties to grow in optimal rate; up to the 10th week plant still did not reach the generative state uniformly and canopy coverage was below 20 percent.