2.3. Optical properties of smoke pa

2.3. Optical properties of smoke particles
The impacts of atmospheric aerosols including smoke particles on radiation depend on their optical properties, mainly aerosol optical depth (AOD) and single scattering albedo (SSA) (Hansen et al., 1997; Kanakidou et al., 2005). The optical properties of aerosol particles depend strongly on the size distribution, morphology,chemical composition, and mixing states (Reid et al., 2005a,b; Jacobson, 2001). AOD is the extinction resulting from absorption and scattering of radiation by the aerosol in a column. SSA is the ratio of scattering to the sum of scattering and absorption and is an indicator of intensity of absorption capacity of aerosol. A value of unity (one) represents pure scattering aerosols. The smaller the SSA value is, the stronger the aerosol absorption is. Aerosol optical properties depend on particle size distribution and radiation wavelength. The magnitude and variations of these two optical properties have been reported for wildfires and controlled biomass burning in a number of climate zones. The AOD of 0.75 (Ross et al., 1998) and SSA from 0.82 for young smoke and 0.94 for aged smoke (Eck et al., 1998) at about 550 nm were obtained from the Smoke, Clouds and Radiation-Brazil (SCAR-B) during the 1995 biomass burning season in Amazon. Comparable values were also obtained from the Aerosol Robotic Network (AERONET) measurements during the SAFARI 2000 dry season campaign in southern Africa (Eck et al., 2003). The maximum AOD at 550 nm ranged from 0.52 to 0.87 with SSA at 440 nm ranging from 0.92 to 0.98 for observations at a number of sites across eastern Europe, northern Scandinavia, and Svalbard near the Arctic (Lund Myhre et al., 2007). The mean AOD at 500 nm for April 2008 at two AERONET boreal sites in Alaska was 0.28 with maximum daily values of about 0.8 and SSA at 440 nm ranged from 0.91 to 0.99 with an average of 0.96 for observations in 2004 and 2005 (Eck et al., 2009). The optical properties of smoke may differ substantially among different climate zones and smoke age. Eck et al. (2003) compared optical properties of four biomass burning events (Table 2). Two of them (Zambia and Brazil) were tropical fires with the fuel types of savanna and mixed forest and pasture. Others (Maryland and Moldova) were boreal fires with the fuel types of forest and peak. There are noticeable differences between the tropical and boreal fires. The particle sizes with the largest volume are smaller for the tropical fires (0.15 and 0.18 lm) than the boreal fires (0.2 and 0.25 lm). The smoke was a mixture of young and aged for the tropical fires, but aged for the boreal ones. AOD, which decreases with wavelength, is the same for all fire cases at 500 nm, but larger (smaller) at the wavelengths >500 nm (

Results (English) 1:

2.3. Optical properties of smoke particles
The impacts of atmospheric aerosols including smoke particles on radiation depend on their optical properties, mainly aerosol optical depth (AOD) and single scattering albedo (SSA) (Hansen et al., 1997; Kanakidou et al., 2005). The optical properties of aerosol particles depend strongly on the size distribution, morphology,chemical composition, and mixing states (Reid et al., 2005a,b; Jacobson, 2001). AOD is the extinction resulting from absorption and scattering of radiation by the aerosol in a column. SSA is the ratio of scattering to the sum of scattering and absorption and is an indicator of intensity of absorption capacity of aerosol. A value of unity (one) represents pure scattering aerosols. The smaller the SSA value is, the stronger the aerosol absorption is. Aerosol optical properties depend on particle size distribution and radiation wavelength. The magnitude and variations of these two optical properties have been reported for wildfires and controlled biomass burning in a number of climate zones. The AOD of 0.75 (Ross et al., 1998) and SSA from 0.82 for young smoke and 0.94 for aged smoke (Eck et al., 1998) at about 550 nm were obtained from the Smoke, Clouds and Radiation-Brazil (SCAR-B) during the 1995 biomass burning season in Amazon. Comparable values were also obtained from the Aerosol Robotic Network (AERONET) measurements during the SAFARI 2000 dry season campaign in southern Africa (Eck et al., 2003). The maximum AOD at 550 nm ranged from 0.52 to 0.87 with SSA at 440 nm ranging from 0.92 to 0.98 for observations at a number of sites across eastern Europe, northern Scandinavia, and Svalbard near the Arctic (Lund Myhre et al., 2007). The mean AOD at 500 nm for April 2008 at two AERONET boreal sites in Alaska was 0.28 with maximum daily values of about 0.8 and SSA at 440 nm ranged from 0.91 to 0.99 with an average of 0.96 for observations in 2004 and 2005 (Eck et al., 2009). The optical properties of smoke may differ substantially among different climate zones and smoke age. Eck et al. (2003) compared optical properties of four biomass burning events (Table 2). Two of them (Zambia and Brazil) were tropical fires with the fuel types of savanna and mixed forest and pasture. Others (Maryland and Moldova) were boreal fires with the fuel types of forest and peak. There are noticeable differences between the tropical and boreal fires. The particle sizes with the largest volume are smaller for the tropical fires (0.15 and 0.18 lm) than the boreal fires (0.2 and 0.25 lm). The smoke was a mixture of young and aged for the tropical fires, but aged for the boreal ones. AOD, which decreases with wavelength, is the same for all fire cases at 500 nm, but larger (smaller) at the wavelengths >500 nm (<500 nm) for the tropical fires than the boreal ones. SSA, which is much less dependent on wavelength, is smaller for the tropical fires than the boreal ones, indicating that young smoke has stronger absorption than aged smoke. AOD of smoke particles increases with humidity (e.g., Jeong et al., 2007), a hygroscopic property. As relative humidity (RH) increases, aerosols absorb water from the air, which increases the particle size and therefore increases the particle scattering cross section. Hygroscopic growth is only important for RH greater than about 40% and, at a given RH, varies with particle solubility (Reid et al., 2005b).

Results (English) 2:

2.3. Sifat optik asap partikel
Dampak aerosol atmosfer termasuk partikel asap pada radiasi tergantung pada sifat optik mereka, kedalaman optik terutama aerosol (AOD) dan tunggal hamburan albedo (SSA) (Hansen et al, 1997;.. Kanakidou et al, 2005) . Sifat optik partikel aerosol sangat bergantung pada distribusi ukuran, morfologi, komposisi kimia, dan pencampuran negara (Reid et al, 2005a, b;. Jacobson, 2001). AOD adalah kepunahan akibat penyerapan dan hamburan radiasi oleh aerosol dalam kolom. SSA adalah rasio hamburan dengan jumlah dari hamburan dan penyerapan dan merupakan indikator intensitas kapasitas penyerapan aerosol. Nilai persatuan (satu) merupakan aerosol hamburan murni. Semakin kecil nilai SSA adalah, semakin kuat penyerapan aerosol adalah. Aerosol sifat optik tergantung pada distribusi ukuran partikel dan radiasi panjang gelombang. Besarnya dan variasi dari dua sifat optik ini telah dilaporkan untuk kebakaran hutan dan dikendalikan pembakaran biomassa di sejumlah zona iklim. The AOD 0,75 (Ross et al., 1998) dan SSA dari 0,82 untuk merokok muda dan 0,94 untuk merokok usia (Eck et al., 1998) pada sekitar 550 nm diperoleh dari Asap, Awan dan Radiasi-Brazil (SCAR- B) selama 1995 biomassa musim terbakar di Amazon. Nilai Sebanding juga diperoleh dari Aerosol Robotic Network (AERONET) pengukuran selama kampanye SAFARI 2000 musim kemarau di Afrika Selatan (Eck et al., 2003). The AOD maksimum pada 550 nm berkisar 0,52-0,87 dengan SSA pada 440 nm berkisar 0,92-0,98 untuk pengamatan di sejumlah situs di seluruh Eropa Timur, Skandinavia utara, dan Svalbard dekat Kutub Utara (Lund Myhre et al., 2007). Mean AOD pada 500 nm untuk April 2008 di dua lokasi boreal AERONET di Alaska adalah 0,28 dengan nilai harian maksimum sekitar 0,8 dan SSA pada 440 nm berkisar 0,91-0,99 dengan rata-rata 0,96 untuk pengamatan pada tahun 2004 dan 2005 (Eck et al ., 2009). Sifat optik asap mungkin berbeda secara substansial antara zona iklim yang berbeda dan usia asap. Eck et al. (2003) dibandingkan sifat optik dari empat peristiwa pembakaran biomassa (Tabel 2). Dua dari mereka (Zambia dan Brazil) adalah kebakaran tropis dengan jenis bahan bakar hutan savana dan campuran dan padang rumput. Lainnya (Maryland dan Moldova) adalah kebakaran boreal dengan jenis bahan bakar hutan dan puncak. Ada perbedaan mencolok antara kebakaran tropis dan boreal. Ukuran partikel dengan volume terbesar yang lebih kecil untuk kebakaran tropis (0,15 dan 0,18 lm) daripada kebakaran boreal (0,2 dan 0,25 lm). Asap adalah campuran muda dan tua untuk kebakaran tropis, tapi untuk yang berusia boreal. AOD, yang menurun dengan panjang gelombang, adalah sama untuk semua kasus kebakaran pada 500 nm, tetapi lebih besar (lebih kecil) pada panjang gelombang> 500 nm (<500 nm) untuk kebakaran tropis daripada yang boreal. SSA, yang jauh lebih sedikit tergantung pada panjang gelombang, yang lebih kecil untuk kebakaran tropis daripada yang boreal, menunjukkan bahwa asap muda memiliki daya serap kuat dari asap tua. AOD partikel asap meningkat dengan kelembaban (misalnya, Jeong et al., 2007), properti higroskopis. Sebagai kelembaban relatif (RH) meningkat, aerosol menyerap air dari udara, yang meningkatkan ukuran partikel dan karenanya meningkatkan penampang hamburan partikel. Pertumbuhan higroskopis hanya penting bagi RH lebih besar dari sekitar 40% dan, pada RH tertentu, bervariasi dengan kelarutan partikel (Reid et al., 2005b).

Results (English) 3:

2.3。烟雾颗粒光学性质
大气气溶胶包括对烟雾粒子辐射取决于它们的光学性能的影响，主要的气溶胶光学厚度（AOD）和单次散射反照率（SSA）（汉森等人。，1997；kanakidou等人。，2005）。气溶胶粒子的光学性质强烈地依赖于粒度分布，形态，化学成分，混合态（瑞德等人。，2005a，B；雅各布森，2001）。AOD是灭绝造成的吸收和列中的气溶胶的散射辐射。SSA是散射的散射和吸收的总和之比是对气溶胶的吸收能力的强度指标。一个团结的价值（一）代表纯散射气溶胶。较小的SSA值，气溶胶的吸收越强。气溶胶光学性质取决于颗粒尺寸分布和辐射波长。的大小与这两个光学性质的变化已被报道用于控制野火和生物质燃烧在一个气候区。0.75 AOD（罗斯等人。，1998）和SSA从0.82和0.94岁的小伙子的烟烟（Eck等。，1998）在约550 nm的烟，云和辐射巴西（SCAR-B）1995的生物质燃烧的季节期间，在亚马逊。从气溶胶机器人网络（AERONET值也得到了类似的Safari 2000）在非洲南部的干燥的季节活动在测量（ECK等人。，2003）。在550 nm的最大和0.52～0。87，SSA在440 nm的范围从0.92到0.98的观测数在东欧，斯堪的纳维亚北部和斯瓦尔巴群岛的位置，靠近北极（Lund迈尔等人。，2007）。平均气溶胶光学厚度在500 nm为2008四月在两个AERONET北方的网站在阿拉斯加是0.28，约0.8和SSA日最大值在440 nm的范围从0.91到0.99，平均为0。96，观察2004和2005（ECK等人。，2009）。烟雾的光学特性可能会有所不同，在不同的气候带，烟龄。埃克等人。（2003）相比，光学性能四生物质燃烧事件（表2）。其中两个（赞比亚和巴西）是热带火灾和燃料类型的草原和混合森林和牧场。其他（马里兰州和摩尔多瓦的寒带森林火灾）和峰值燃料类型。有明显的差异之间的热带和寒带的火灾。颗粒的尺寸和体积最大的是热带火灾规模较小（0.15和0.18的LM）比北方的火灾（0.2和0.25流明）。烟是一个青年和老年的热带森林大火的混合物，但老年人对北方的。AOD，它随波长的减小，是所有火灾案例500 nm相同，但更大的（小）在波长大于500 nm（小于500 nm）的比北方的热带森林大火。SSA，这是不依赖于波长，是热带火灾比北方的小，表明年轻的烟烟比老年人强吸收。随着湿度的增加（例如，烟雾粒子AOD Jeong等人。，2007），吸湿性。作为相对湿度（RH）的增加，气溶胶吸收空气中的水分，使粒径增大，因此提高了粒子的散射截面。吸湿性生长是唯一重要的相对湿度大于40%，在一个给定的相对湿度，颗粒的溶解度变化（瑞德等人。，2005b）。