LDEO Seismology: Long-Period Noise

KMBO-IU , LH2-00

Noise Levels at Different Periods

The table below gives the decibel 10% noise level (in db) for each month in several period bands. The 10% noise level is defined as the signal level not exceeded 10% of the time, based on hourly measurements. Each entry in the table is color coded with reference to the New Low Noise Model (NLNM, Peterson, 1993):
navy, -6 db < value-NLNM < -3 db
blue, -3 db < value-NLNM < 3 db
aqua, 3 db < value-NLNM < 6 db
lime, 6 db < value-NLNM < 9 db
yellow, 9 db < value-NLNM < 12 db
orange, 12 db < value-NLNM < 15 db
red, 15 db < value-NLNM < 20 db
fuchsia, 20 db < value-NLNM < 25 db
silver, value-NLNM < -6 db, value-NLNM > 25 db

Black indicates that there was an insufficient number of hourly measurements to calculate a noise level.

Noise levels (PSD) in decibels
Month Chan. Qual. # obs. 518s 439s 373s 316s 268s 228s 193s 164s 139s 118s 100s 85s 72s 61s 52s 44s 37s 32s 27s 23s 19s 16s 14s 12s 10s

201810 LH2-00 AR 342 -140 -143 -134 -145 -147 -147 -150 -152 -153 -155 -154 -156 -157 -158 -159 -160 -162 -162 -164 -164 -161 -157 -156 -156 -153

201809 LH2-00 AR 719 -140 -142 -137 -143 -149 -148 -150 -151 -154 -154 -154 -157 -157 -159 -161 -162 -164 -166 -166 -166 -161 -157 -156 -155 -152

201808 LH2-00 AR 476 -141 -142 -145 -148 -149 -152 -152 -155 -156 -158 -158 -160 -161 -162 -163 -165 -167 -168 -170 -169 -163 -158 -155 -156 -154

201807 LH2-00 AR 690 -141 -139 -138 -147 -143 -150 -151 -151 -154 -155 -155 -157 -158 -160 -162 -163 -165 -167 -168 -166 -159 -155 -154 -154 -150

201803 LH2-00 AR 21 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999

201802 LH2-00 AR 50 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999

Month	Chan.	Qual.	# obs.	518s	439s	373s	316s	268s	228s	193s	164s	139s	118s	100s	85s	72s	61s	52s	44s	37s	32s	27s	23s	19s	16s	14s	12s	10s
201810	LH2-00	AR	342	-140	-143	-134	-145	-147	-147	-150	-152	-153	-155	-154	-156	-157	-158	-159	-160	-162	-162	-164	-164	-161	-157	-156	-156	-153
201809	LH2-00	AR	719	-140	-142	-137	-143	-149	-148	-150	-151	-154	-154	-154	-157	-157	-159	-161	-162	-164	-166	-166	-166	-161	-157	-156	-155	-152
201808	LH2-00	AR	476	-141	-142	-145	-148	-149	-152	-152	-155	-156	-158	-158	-160	-161	-162	-163	-165	-167	-168	-170	-169	-163	-158	-155	-156	-154
201807	LH2-00	AR	690	-141	-139	-138	-147	-143	-150	-151	-151	-154	-155	-155	-157	-158	-160	-162	-163	-165	-167	-168	-166	-159	-155	-154	-154	-150
201803	LH2-00	AR	21	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999
201802	LH2-00	AR	50	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999